Biology Flashcards
Semi conservative replication
2 DNA strands unzip and each are a template for complementary nucleotides to form new strands ( 2 identical chromosomes)
Topoisomerases
Relax supercoiling
Helicase
Disrupts H-bonds between bases which unzips DNA
DNA primase
Forms short RNA primer which initiates binding of DNA polymerase to parent strands
DNA polymerase
Binds to parent strand and travels 5’ to 3’
Parent strands are antiparallel which means?
DNA polymerases want to go in opposite directions
Leading strand is synthesized __________?
Continuously
Lagging strand is synthesized in ___________?
Okazaki fragments ( 200-2000 base pairs separated by 50 base pair gaps )
Ligase fills gaps between __________?
Okazaki fragments
_______________ replaces RNA primer with DNA nucleotides
Another DNA polymerase
DNA
Single origin of replication and 2 replication forks move in opposite directions around chromosome
Eukaryotic DNA
Multiple linear chromosomes sopercoiled around histone proteins, multiple origins of replication
Telomeres
Numerous at ends of eukaryotic chromosomes and prevent damage to coding regions
________ lost from ends of chromosomes with each replication
1
When the last telomere is lost, more replication causes chromosome damage which is associated with?
Aging
Centromere
Area of a eukaryotic chromosome with repeating bases
__________ remain connected at the centromere until disjunction in mitosis or meiosis
2 sister chromatids
Okazaki fragments are much shorter in eukaryotes because of differences in ______?
Polymerases
Transcription ______ to ______?
DNA to RNA
Translation ______ to __________?
RNA to amino acids sequence of proteins
______ of genome transcribed
Only a fraction
Transcribed section of genome?
Gene
Adjacent genes expressed together? (name)
Operon
3 steps of Transcription?
Initiation, Elongation, and Termination
Transcription: Initiation
Transcription factors bind to the promoter site (TATA box) at start of gene
___________ binds to a protein initiation factor to be activated
RNA polymerase
Transcription: elongation
Helicase unwinds gene from nucleosome (histones) and unzips
RNA polymerase disrupts __________ between base pairs
H- bonds
RNA polymerase travels
3’ to 5’
Transcription: termination
RNA polymerase reaches terminator poly-A sequence, releases primary mRNA transcript
Prokaryotes: mRNA translated to ________ by____________ in__________ ?
Protein
Ribosomes
Cytoplasm
Eukaryotes: mRNA posttranscriptionally modified by________?
miRNA
5’ ___________ added to 5’ end of the _________________
Poly-A tail added to __________end
Guanine cap.
Primary transcript
3’
snRNPs
“snurps”
Small nuclear ribonucleoproteins 
miRNA
microRNA
Spliceosomes
Large ribonucle o protein complexes with RNA loops, assembled from snRNPs and proteins
Introns
X
Exons
X
98% of human genome is _________________
Noncoding sequences
Noncoding sequences: __________, __________, and __________
Regulate gene expression
Are transposons (jumping genes)
Have no known function
tRNA, rRNA, and other small regulatory or catalytic RNAs are NOT ________________
Translated
Every 3 nucleotides in mRNA
Codon
Each codon codes for an __________?
Amino acid
Short RNAs, form 3 loop Cloverleaf structure and at the end of the middle loop is an anti-codon
tRNA
Determines amino acid attachment to tRNA, and complementary to mRNA codon
Anti-codon
tRNA is transported to___________?
Cytoplasm
Enzymes attach specific__________________ to each tRNA
Amino acid
Complex protein/RNA structures that catalyze translation of the nucleotide sequence of mRNA into amino acid sequence of proteins
Ribosomes
Composed of two subunits, one large and one small, made of RNA and proteins
(Subunits transcribed and assembled in nucleus and then exported to ER or cytoplasm)
Ribosomes
Ribosomes: small subunit binds to ________________?
mRNA
Ribosomes: large subunit, 3 active sites ?
A : binds to 1st Aminoacyl tRNA
P : binds to 2nd tRNA by peptide binds
E : where 1st tRNA exits
Translation:
3 steps - ___________ ,__________, & ___________
Initiation
Elongation
Termination
____________ : small ribosomal subunit binds 5’ end of mRNA -> initiator tRNA binds to AUG mRNA start codon -> large ribosomal subunit binds to small subunit, with initiator tRNA in the “P” site of the ribosome
Initiation
__________ : new tRNA (complementary to 2nd codon) binds in “A” site of ribosome -> ribosome shifts 3 base pairs toward 3’ end of mRNA -> “P” site tRNA is ejected and a peptide bond forms between the 1st and 2nd amino acids -> 2nd tRNA is now in “P” site with a dipeptide attached -> new tRNA binds to “A” site -> elongation repeats itself
Elongation
__________ : ribosome reaches stop codon -> protein release factors bind to codon and release polypeptide -> ribosome disassemble
Termination
__________ : cleave initiator methionine ; cleave preproteins into polypeptides or add ligands (glycosylation, methylation, phosphorylation)
Posttranslation protein modification
_____________
- “words” in DNA/RNA language
- translated into amino acids, the protein language
- 3 nucleotides long with 4 bases
- 4^3 or 64 possibilities
Codons
________________
- complementary to DNA codons (except U replaces T)
mRNA codons
The 3 stop codons ________, ________, & ________.
- trigger end of translation and ribosomal separation
- do not bind to amino acids
UAA
UAG
UGA
______ (#) tRNAs bind specifically to one of 20 amino acids
61
________________
- evolution favors genetic code in which changes in 3rd base position do no result in a change in amino acid sequence (protects from nearly 1/3 of possible mutations)
- example GAU, GAC, GAG, & GAA all code for alanine
Redundancy in genetic code
________________
single base deletions/insertions can cause transcription frame shift -> entire gene past the mutation no longer codes for the correct protein
Reading frame mutations
Genes are regulated through ________ feedback (activation or induction) or ________ feedback (repression)
Positive
Negative
Switching __________ on/off is key to development and differentiation
Genes
____________ is a sequence of DNA containing a cluster of genes under the control of a single promoter
- gene regulation in prokaryotes
- promoter region, operator region, and several genes related to a particular pathway
Operon
__________ is binding site for RNA polymerase in Operon
Promoter
__________ is on/off switch in Operon
Operator
______ operon (E.coli lactose digestion
positive feedback
repressor protein binds to operator -> lactose binds repressor protein, altering its shape -> releasing protein from operator -> RNA polymerase transcribes lac operon genes -> when lactose is gone, repressor rebinds to operator halting expression
lac
________ operon (enzymes to synthesize tryptophan)
negative feedback
repressor protein binds to operator when it combines with tryptophan (when tryptophan is abundant)
trp
Acetylation of histones in nucleosome cause DNA to _________
- genes can be expressed
Uncoil
Deacetylation/Methylation os histones causes DNA to __________
- stop genes expression
Supercoil
____________
- proteins bind to promoter to start transcription
Transcription factors
____________
- DNA sequences that interact with promoter to allow expression
Control elements
Groups of control elements are called __________
enhancers
____________ bind enhancers and transcription factors which form initiation complex with RNA polymerase at promoter
Mediator proteins
____________ bind near the promoter, preventing the initiation complex or RNA polymerase binding
Repressor proteins
____________
- increases gene expression
- plays critical role in evolution because one version can remain intact while the other changes (genetic drift)
Gene duplication
____________ can interfere with transcription or mRNA to stop translation
small noncoding RNAs
____________
a DNA molecule coiled around histone proteins (chromatin)
Eukaryotic chromosome
Human chromosome has about ____________ million base pairs (bp)
50 - 250 million
____________
about 200 base pairs wrapped around each histone
Nucleosome
____________
- uncoiled areas of a chromosome
- active gene expression
- light colored in stained microscope images
Euchromatin
____________
- DNA tightly supercoiled
- darkly stained (microscope images)
Heterochromatin
____________
- repetitive noncoding DNA at ends of each chromosome
- protect coding regions from damage over time
Telomeres
____________
- DNA sequences
- stay connected after replication
- hold 2 sister chromatids together until disjunction in mitosis or meiosis
Centromere
____________
- fibers attach to the chromatids at the centromere
Kinetichore
______________________
- alteration of naturally occurring genomes in organisms for medical, pharmaceutical, agricultural, environmental, or general research purposes
- genes isolated from one species or novel genes used to transform another species
- human insulin gene was inserted into E.coli to create insulin-producing bacteria
Recombinant DNA technology
(biotechnology, genetic engineering or modification)
____________
- inserting foreign DNA into a plasmid (extrachromosomal DNA) or bacteriophage virus -> transforms the bacteria
- genes of interest linked to a marker (ex: antibiotic resistance, phosphorescence)
-inserting foreign DNA into the plasmid or viral genome uses restriction enzymes which cleave DNA at specific sequences where the ends of segments are offset by several bases -> projecting bases (sticky ends) reanneal with foreign DNA in the plasmid or viral DNA
Bacterial transformation
____________
- use different restriction enzymes to cut genomes into segments -> separated by electrophoresis -> used to locate/isolate specific genes
DNA libraries
____________
- made using reverse transcriptase & DNA polymerase to make DNA from mRNA
- a specific cDNA library reflects proteins synthesized by a cell at that stage in the cell cycle, a step in proteomic research or to isolate specific genes
cDNA
____________
- used to clone/amplify DNA sequences
- requires primers (complementary to 3’ ends of target strands
- primers facilitate polymerization
- DNA is heated, polymerized, reheated, and repolymerized, doubling the DNA each time
PCR
____________
- spliced next to a promoter region to assure their expression in host cells
cloned genes
____________
- having 2 copies of the genome
- zygotes
- somatic cells
diploid
____________
- having one copy of the genome
- gametes
haploid
____________
- unit of heredity
- sequence of DNA
- codes for protein or nontranslated RNA
Gene
____________
- one of several variants of a gene
- results from inherited mutations of a gene
Allele
____________
- outward expression of a trait
- morphological, physiological, or behavioral
Phenotype
____________
- the actual combination of possible alleles of a gene
genotype
____________
- having 2 identical alleles of a gene
homozygous
____________
- having 2 different alleles of a gene
heterozygous
____________
- position of a gene on a chromosome
locus
____________
- all the genes in an individual of a species
genome
____________
- all the alleles of a gene or set of genes in a population
gene pool
____________
- shows in phenotype when homozygous or heterozygous
dominant
____________
- expressed only if there are 2 of the recessive alleles
recessive
____________
- heterozygotes show distinct or intermediate phenotype
Incomplete dominance
____________
- both alleles expressed
- ex: ABO blood groups (AB blood)
Codominance
____________
- degree to which genotype is expressed in the phenotype of a fraction of population with that genotype
- ex: 50-70% women with BRCA1 mutation develop breast cancer
Penetrance
____________
- degree of phenotype variation among individuals with same genotype
Expressivity
____________
- a single gene affecting several traits
Pleiotropy
____________
- 1 gene influencing the phenotype of another gene
Epistasis
____________
- Mendel noticed that results of monohybrid crosses were always a 3:1 dominant:recessive ratio
- concluded that each trait was controlled by 2 copies of a gene and gametes randomly receive 1 copy of each gene
Random segregation
____________
- 9:3:3:1 phenotypic results of dihybrid crosses involving 2 heterozygous traits
- concluded genes on separate chromosomes sort independently
Independent assortment
____________
- loci on the same chromosomes that do not sort independently
linked genes
____________
- sections of DNA from 1 chromosome crossover to its homologue, altering predicted ratios by changing linkage patterns
Recombination
____________
- males inherit X chromosome from mother and Y chromosome from father
- males inherit X cannot be heterozygous for sex-linked traits
Sex-linkage
____________
- extranuclear inheritance
- inherited matrilineally
mitochondrial genes
____________
- diploid eukaryotic cell division to produce 4 haploid gametes
meiosis
____________
- in diploid cell, replicated homologous pairs unite in synapse -> from tetrads comprised of 4 chromatids, connected by synaptonemal protein complex -> recombination, trading segments of paternal and maternal homologues can occur -> homologous chromosomes separate -> cell divides, forms 2 haploid cells
1st meiotic division
____________
- replicated chromosomes line up individually along equator -> chromatids are pulled apart and the resulting cells for 1n gametes
2nd meiotic division
____________
- eukaryotic cell divides, forming identical 2n cells
- replicated chromosomes line up singly at equator of cell -> chromatids disjoin -> cytokinesis form daughter cells
- reproduction in unicellular eukaryotes
- growth & repair in multicellular eukaryotes
Mitosis
Cell Cycle : ________, ________, ________, ________, & ________
Interphase
Prophase
Metaphase
Anaphase
Telophase
____________
- in breeding experiments, normal traits without induced mutations
Wild type
____________
- between 2 individuals heterozygous for a gene
- results in 1:2:1 genotypic and 3:1 phenotypic ratios in simple dominance genes
- incomplete dominance traits yield a 1:2:1 ratio for both genotype and phenotype
monohybrid cross
____________
- parents heterozygous for 2 unlinked genes
- 9:3:3:1 phenotypic ratio
dihybrid cross
____________
- a cross between a dominant individual of unknown genotype with a known recessive (if any recessive offspring, dominant parent must be heterozygous
testcross
____________
- breeding offspring with parent to retain desirable phenotypes
backcross
____________
- rates of recombination determine distances between linked genes
- restriction enzyme library hybridization provides more detail
- genome sequencing provides most detail
gene mapping
____________
- analysis of a trait through multiple generations
pedigree analysis
____________
- statistically determines allele frequencies in population
Hardy -Weinberg equilibrium
Hardy-Weinberg equilibrium conditions include, ________, ________, ________, ________ & ________ (prevent population from evolving)
-if 1 or more conditions not met then population undergoes microevolution (change in allele frequencies)
large population
random mating
no natural selection
no mutation
no gene flow
____________
- biometric statistical methods determine allele frequencies for multiple-allele genes or polygenic traits
quantitative genetics
Hardy-Weinberg equilibrium
p =
q =
p^2 =
2qp =
q^2 =
__ + __ =
__ + ___ + __ =
p = frequency of dominant allele
q = frequency of recessive allele
p^2 = frequency of homozygous dominants
2qp = frequency of heterozygotes
q^2 = frequency of homozygous recessives
p + q = 1
p^2 + 2qp + q^2 = 1
____________
- fundamental unit of life capable of carrying out all life functions
Cell
____________
- cytoplasm, cell membrane, single circular chromosome, ribosomes
- Often cell wall, flagella, or other external structures
- Bacteria and Archaea
- Unicellular
Prokaryotes
____________
- complex cells, numerous internal membrane-bound organelles, multiple complex chromosomes contained inside nucleus
- Animals, Plants, & Fungi
Unicellular & Multicellular Species
Eukaryotes
_______________
- earliest eukaryote engulfed or was invaded by smaller prokaryote which continue to function inside host cell, conferring higher fitness
- Explains evolution of eukaryotes, based largely on evidence from mitochondria and chloroplasts, which contain their own DNA and ribosomes similar to those found in prokaryotes
Endosymbiosis
_______________
- viscous, intracellular medium
- ~70% water
- Biochemical/mineral solutes
Cytoplasm
_______________
- composed of RNA and protein
- sites of proteins synthesis (mRNA translation)
- suspended and cytoplasm are embedded in ER or other internal membrane
Ribosomes
_______________
- phospholipid bilayer
- hydrophilic on both internal and external cell surfaces
- hydrophobic in the membrane interior
- contains cholesterol & proteins
Plasma membrane
_______________
- double membrane
- Contains DNA and regulatory proteins
Nucleus
_______________
- inside nucleus
- site of rRNA synthesis and ribosome assembly
Nucleolus
_______________
- aerobic cellular respiration
- Double membrane structure
- Krebs cycle occurs in matrix
- Electron transport chain proteins embedded in inner membrane
Mitochondria
_______________
- breakdown cellular waste for export and provide digestive function
- Acidic and filled with digestive enzymes (from Golgi body)
Lysosomes
_______________
- convoluted membrane network, dotted with ribosomes
- New peptide has short amino acid sequence that signals chaperone proteins to move the peptide to destination for folding, modification, activation, & export
Rough endoplasmic reticulum (RER)
_______________
- lipid and carbohydrate anabolism
- Ca2+ balance
- detoxification
Smooth endoplasmic reticulum (SER)
_______________
- modifies/packages proteins for export or intracellular delivery
Golgi body
_______________
- oxidative enzymes catalyze fats/toxins
Peroxisomes
_______________
- proteins provide support, shape, intracellular, transport, so motility, cell adhesion, etc.
- Microfilaments (actin) change cell shaped
- Intermediate filaments secure the cytoskeleton, help in cell transport and cell adhesion
- Microtubules (large hollow protein tubes) parts for motor proteins to transport organelles & rearrange shape for division
Cytoskeleton
_______&________
- composed of microtubules attached by basal body
- motility
Cilia
Flagella
_______________
- govern reorganization of cytoskeleton in division
- similar to basal bodies
Centrioles
_______________
- small unchanged molecules and hydrophobic molecules diffuse through membrane
- Ions and larger
- Polar molecules cannot penetrate
Semipermeable plasma membrane
_______________
- due to random movement of molecules
- No energy input
Passive transport
_______________
- movement of solutes in fluid from higher to lower concentration
Diffusion
_______________
- diffusion of water across membranes from hypotonic to hypertonic
Osmosis
_______________
- through transmembrane channel/carrier proteins
- by molecules that cannot permeate membranes
Facilitated diffusion
_______________
- movement of molecules that requires expenditure of ATP energy
Active transport
_______________
- transport substances, through a membrane against a concentration gradient
- Na+/K+ pump
- Proton pump
Pump proteins
_______________
- engulf or expel dissolved substances or particles
Bulk transport (Endocytosis/exocytosis)
_______________
- connexon proteins embedded in plasma membranes of cells, conduits between the cytoplasm of each cell
- ex: allow cardiac cells to coordinate contraction
Gap junctions
_______________
- membrane proteins anchored to Microfilaments cement cells together to form a continuous impermeable surface
- ex: blood brain barrier
Tight junctions
_______________
- proteins hold cells together, form tissues
- interstitial fluid between cells
Desmosomes
3 types of cell-to-cell communication
_______________
_______________
_______________
Juxtacrine signaling
Paracrine signaling
Endocrine signaling
_______________
- Chemical or charge potential communication
- Uses direct cell contact through gap junctions or desmosomes
Juxtacrine signaling
_______________
- Chemical signals between cells in close proximity
- ex: Neurotransmitters between neurons and effector cells
Paracrine signaling
_______________
- Chemical signals via blood
- Cells distant from each other
Endocrine signaling
_______________
- 40% of all cells
- Lines the exterior of body, walls of body openings, body cavities, & glands
- regulates passage of materials into or out of the tissue
- Lubricates with secretions
- Protects from abrasion by rapid regeneration
- Secretes basement membrane of lycoprotein/collagen
Epithelial tissue
Epithelial tissue:
Single layered = __________
Multi layered = __________
Flat = _________
Cubed = __________
Column = _________
Simple
Stratified
Squamous
Cuboidal
Columnar
_______________
- most abundant tissue type
- Forms bones, tendon, ligaments, blood, fat, underlying skin layers, and interstitial matrix (between organs/other structures)
Connective tissue
Connective tissue is derived from _______________
- differentiates to cell types of blood cells, fibroblasts, adipocytes, chondrocytes, osteocytes, macrophages, mast cells
Embryonic mesenchyme
The connective tissue secretes ___________ made of proteins, polysaccharides, & glycoproteins
Extracellular matrix
3 principles of cell theory
_______________
_______________
_______________
- All living organisms are composed of one or more cells.
- Cells are fundamental living things (viruses/organelles are not considered living)
- All cells are products of reproduction of pre-existing cells.
____________ first recognized cells
‘Robert Hooke
_______________ observed cellular reproduction, and questioned spontaneous generation of life
Anton von Leeuwenhoek
____________ was formulated by Schwann, Schleiden, & Virchow in 1830s although the 3rd principle was not fully accepted until Pasteurs experiments in 1850s
Cell theory
_______________
- 2 domains (Archaea & Eubacteria)
- all Unicellular
- Aerobic or anaerobic environments
- Autotrophs or heterotrophs
- Mostly pathogenic or symbiotic species
Prokaryotes
Prokaryotes Classification :
Shape
Spherical = __________
Coccus
Prokaryotes Classification :
Shape
Rod = __________
Bacillus
Prokaryotes Classification :
Shape
Spiral = __________
Spirillus
Prokaryotes Classification :
Grouping
Pairs = __________
Diplo
Prokaryotes Classification :
Grouping
Chains = __________
Strepto
Prokaryotes Classification :
Grouping
Branched clusters = ____________
Staphylo
Prokaryotes Classification :
Cell Wall
____________ have thick peptidoglycan cell walls, & appear stained purple
Gram-positive
Prokaryotes Classification :
Cell Wall
__________ have thin peptidoglycan layer between 2 membranes, and appears stained red/pink (most serious pathogens because lipopolysaccharides on outer membrane’s act as powerful toxins)
Gram-negative
Prokaryotes Classification :
Metabolism
Cannot survive without O2 = ____________
Obligate aerobes
Prokaryotes Classification :
Metabolism
Cannot tolerate O2 = ____________
Obligate anaerobes
Prokaryotes Classification :
Metabolism
Respire with or without O2 = ____________
Facultative anaerobes
____________________
- some prokaryotes produce a protective glycoprotein or carbohydrate capsule around their cell walls
- In some bacteria this forms an adhesive Biofilm
Glycocalyx
____________________
- a thick protein structure protects from adverse conditions
Endospore
____________________
- thin protein filament that helps a bacterium attach to a substrate or host cell
Fimbrae
____________________
- many move using one or more of the structure
- a thin protein filament attached to a spinning base unit
- differs in structure in mechanics from eukaryotic type (which whip back and forth)
- Bacteria can reverse direction by reversing spinning
Flagella
____________________
- mutations that confer resistance
Antibiotic resistance
____________________
- prokaryotes that reproduce as quickly as every 20 minutes
- The rapid reproduction rate, along with a constant rate of mutation, make bacteria, highly adaptable
Adaptability
____________________
- are the most ubiquitous organisms on earth, occupying all possible habitats
Prokaryotes
____________________
- prokaryotic DNA, circular molecule attached to plasma membrane in the Nucleoid Region
- Transcription and translation occur simultaneously in the cytoplasm
Simple genomes
____________________
- small, circular, extragenomic DNA molecules present in the cytoplasm of prokaryotes
- Often contain genes that confer antibiotic resistance
Plasmids
____________________
- in prokaryotes, plasmids may spliced into or out of the genomic chromosome
- this process is mimicked in use of plasmids in biotechnology (recombination)
Transposons
____________________
- cell division in prokaryotes, simple and rapid
- DNA replicates than the cell divides (starting from a single origin of replication)
Binary fission
____________________
- tubular proteins structures protruding from the prokaryotic cell
- Function in cell-cell interactions, and as a conduit for transduction (the exchange or transfer of a copy of a plasmid from one bacterium to another)
Pili
____________________
- proteins encapsulating a small DNA or RNA chromosome
- no metabolic or reproductive processes
- take over metabolic, reproductive mechanisms of host cells
- evolve in response to changes in hosts
- adapt rapidly to immune responses
Viruses
Viruses are classified according to __________ , ____________, & ______________ .
Host type (prokaryote, or eukaryote) - host range
Capsule composition and structure
Nucleic acid type
Viruses outside the host are called ____________ .
Virions
____________________
- protein capsid surrounding DNA
- Complex proteins tail sheath to inject, viral DNA into host bacterium
- Tail fibers bond to bacterial cell wall
Bacteriophage virus
____________________
- misfolded proteins
- enter a host, cause chain reaction of similar proteins misfolding
- Creutzfeldt-Jakob & bovine spongiform encephalopathy are diseases
Prions
____________________
- tiny circular RNAs that infect plants, but do not contain genes
- their presence in a host cell activates RNA silencing mechanisms, halting proteins synthesis
Viroids
____________________
- Insert their nucleic acid into host cells, co-opting cells infrastructure to synthesize viral proteins and genomes, which self assemble and exit to infect other cells
Viruses
Many viruses alternate between __________cycle & __________ cycle
Lytic cycle
Lysogenic cycle
____________________
- complete takeover of the host cell transcription and translation process
- Rapid production of new viruses
- Rupture of host cell releases new viruses
Lytic cycle
____________________
- viral DNA splices into host genome
- cell continues to function, copying, viral genome (prophage) with each division
- Lytic cycle follows
Lysogenic cycle
____________________
- prophage causes harmless bacterium to become pathogenic
Lysogenic conversion
____________________
- viral RNA is translated on entry into cell
Eukaryotic RNA viruses
____________________
- RNA viruses that translate reverse transcriptase, an enzyme that synthesize DNA from RNA
- the DNA can then enter a lysogenic cycle
Retroviruses
____________________
- A retroviral infection that infects specific cells of the human immune system, and causes acquired immunodeficiency syndrome (AIDS)
- Infects helper T cells, dendritic cells, & macrophages
- Helper T cell numbers decline I
- Increase susceptibility to infection & certain cancers
Human immunodeficiency virus (HIV)
HIV is coated with __________ proteins in lipid membrane remaining from past host cell that fuses with new host cell plasma membrane, allowing viral capsid to enter
Docking
HIV inside the host cell (steps)
- viral RNA translated by cytoplasmic ____________
- ________________ catalyzes the synthesis of DNA from the viral RNA template
- ________________ catalyzing splicing of the viral DNA into host cell DNA
- Virus is in __________ phase (hiding) in the host cell genome
- Virus enters __________ phase producing billions of new virions, spreading throughout the hosts immune system
Ribosomes
Reverse transcriptase
Integrase
Latent phase
Lytic phase
____________________
- between and during cell division, cells go through distinct phases
- Generation time
- Time between divisions
- Days in eukaryotes
Cell cycle
____________________
- between cell divisions
- Contains 3 sub phases
Interphase
____________________
- transcription/translation of genes for cell growth/function
G1 phase (1st gap)
____________________
- DNA replication
- Subphase in interphase
S phase (synthesis)
____________________
- similar to G1 but cell division is certain
- mitosis follows this phase
G2 phase (2nd gap)
In cells that undergo growth arrest, terminal division followed by G1 is followed by __________ (cell continues to function but no more growth or DNA replication)
G0
In damaged cells, G2 is followed by ____________
Apoptosis
Transition between sub phases is regulated by a series of cell cycle ____________ , proteins that inhibit or prevent synthesis of enzymes that trigger the next phase.
Checkpoints
____________________
- asexual reproduction of unicellular eukaryotes
- Development, growth, and repair in multicellular eukaryotes
Mitosis
M phase
____________________
- Replicated chromosomes supercoil (characteristic X shape of replicated sister chromatids connected at centromere)
- Nuclear membrane dissolves
- Cytoskeleton rearranges microtubules grow outward from the centrioles to form mitotic spindle
Prophase
____________________
- Centrioles migrate to poles
- Spindle fibers attach to kinetochores of each chromatid
- replicated chromosomes lineup individually at equator
Metaphase
____________________
- disjunction
- Sister chromatids split at centromere and pulled to each pole
Anaphase
____________________
- chromosomes uncoil then nuclear membranes form around 2 nuclei
Telophase
____________________
- Cell contents divide
- Cleavage furrow at equator as plasma membrane pinches into 2 cells
Cytokinesis
____________________
- forms gametes (1n) in sexual reproducing eukaryotes
Meiosis
____________________
- sperm/ova
- haploid (1n)
Gamete
____________________
- diploid (2n)
- homologous pairs of each chromosome
Zygote & somatic cells
A human gamete has _____ chromosomes
A human diploid cell has _____ chromosomes
23
46
Human cells have _____ autosomes & _____ sex chromosome
22
1
____________________
- begins with G2 germ cells in gonads
- consists of 2 cell divisions
Meiosis
____________________
- replicated chromosomes supercoil
- nuclear membrane dissolves
- spindle fibers link centrioles to centromeres
- homologous pairs form tetrads (4 chromatids) and process of synapsis
- recombination (crossing-over) possible at Chiasmata (homologous chromatids intersect)
- exchange bits of maternal/paternal chromatids
Prophase I
____________________
- synapsis continues
- homologous chromosome pairs line up at equator
Metaphase I
____________________
- homologous chromosome pairs are split apart toward poles
Anaphase I
____________________
- reduction division (chromosome number halved)
- cell completes division I
- daughter cells haploid, nonidentical (chromosomes still replicated)
Telophase I
____________________
- similar to mitosis begins with 2 haploid cells
Meiosis II
____________________
- chromosomes supercoil
- Nuclear membrane dissolves
- Spindle forms
Prophase II
____________________
- chromosomes lineup individually across equator
Metaphase II
____________________
- chromatids split into separate on replicated chromosomes (disjunction), pulled toward poles
Anaphase II
____________________
- chromosomes uncondensed
- nuclear membrane forms, followed by cytokinesis
- result is 4 non-identical haploid gametes
Telophase II
____________________
- Spermatogonia line seminiferous tubules ——>
- Testosterone triggers mitosis ——->
- 2n spermatocytes ——->
- Meiosis ——->
- 1n spermatids ——->
- Grow flagellum ——->
- Spermatozoa
Spermatogenesis
____________________
- Oogonia in ovarian follicles, outer cortex of ovary ——->
- Primary oocytes stop in metaphase II before birth ——->
- Post puberty, several follicles undergo oogenesis monthly ——->
- 1 forms of ovum
- oogenesis divisions unequal, all cytoplasm in each division goes to 1 cell ——->
- Forms 3 polar bodies and 1 secondary oocyte ——->
- Becomes ovum upon fertilization
Oogenesis
____________________
- sperm survive up to 5 days in female reproductive tract
- oocyte viable for 12-24 hours
- many sperm reach ovum and uterine tube ——->
- Enzymes break down corona radiata/zona pellucida around oocyte ——->
- 1st sperm to reach oocyte membrane binds sperm receptors ——->
- Ca2+ release prevents additional sperm entry ——->
- oocyte completes meiosis II ——->
- Nuclei fuse to become 2n zygote
Fertilization
____________________
- zygote divides as it passes uterine tube ——->
- Forms blastocyst ——->
- Implants in ovary ——->
- Endometrial capillaries erode ——->
- Exchange nutrients/waste with maternal blood ——->
- Blastocyst hCG causes corpus luteum production of progesterone/estrogen
Implantation
____________________
- fetal/maternal capillaries intertwine ——->
- form placenta (fetal chorionic villi grow into endometrium)
- allantois forms umbilical cord, & connects embryo to placenta
Placentation
True or false:
No contact between maternal and fetal blood
True
Placenta takes oversecretion of progesterone/estrogen by ________
9 weeks
____________________
- ~40 weeks from 1st day of last menstruation
- in 1st 9 weeks the zygote develops into embryo with limbs in early organ systems
- after 9 weeks the fetal development continues until 37-40 weeks
- Earlier birth is pre-term
Gestation (pregnancy)
____________________
- Labor, uterine contractions ——->
- Causes cervical dilation ——->
- Baby exits through vagina ——->
- Placenta separates from uterine wall and exits separately
Parturition (birth)
____________________
- postfertilization, the zygote divides rapidly (cleavage) by mitosis without G1 & G2 stages into a morula (solid ball of progressively smaller cells)
Morulation
____________________
- after 6 - 8 divisions the cells of the Morula flatten, forming a tight sphere of cells (blastula) around a fluid filled cavity (blastocoel)
- blastula contains outer layer (trophoblast) and inner cell mass that becomes embryo and amniotic tissue
- it’s complete by day 7 when implantation occurs
Blastulation
____________________
- ~day 12 the gastrula forms
- cells derived from inner cell mass then divide into 3 germ layers (Ectoderm, Mesoderm, & Endoderm)
- 1 part of trophoblast forms chorionic villi
- 1 part of trophoblast forms archenteron
- a groove (blastopore) in the archenteron becomes anus in deutrostomes
- a groove (blastopore) in the archenteron becomes mouth in protostomes
Gastrulation
____________________
- neural tube development (chordates)
- mesoderm/ectoderm cell signaling interactions cause ectoderm to form neural plate ——-> folds to become dorsal nerve cord
Neurulation
____________________
- 3 primary germ layers differentiate into distinct tissues and organs
Organogenesis
The 3 primary germ layers are :
_______________
_______________
_______________
Ectoderm
Mesoderm
Endoderm
____________________
- Nervous system (also pituitary/pineal glands)
- Integumentary system (mucous membranes/outer layer of skin, mouth, pharynx, anus)
- Epithelial derived structures (hair, follicles, sweat/memory glands, cornea/lens)
- Adrenal medulla
- Neural crest cells migrate to become epithelium and portions of jaw, teeth, and heart valves
Ectoderm
____________________
- Bones/connective tissue ( cartilage, tendons, ligaments, blood, dermis)
- Muscle
- Circulatory, Lymphatic, Reproductive, Urinary systems (blood vessels, spleen, reproductive organs, kidneys, bladder, smooth muscle)
- Adrenal cortex
- along notochord, it forms somites ——-> become vertebral column & muscles of spine & rib cage
Mesoderm
____________________
- respiratory system (epithelia of trachea, bronchi, alveoli)
- Digestive system (epithelia of esophagus, stomach, intestines)
- Liver, Pancreas, Lining of Thymus, Thyroid/Parathyroid
- Epithelial lining of urethra, bladder, & reproductive systems
Endoderm
Zygote is _______________ (differentiates into every cell type)
Totipotent
After 5th division, embryonic morula stem cells are _______________ (into 1 of 3 germ layer tissues)
Pluripotent
Cells later reach determined state, which means?
There is no change to different cell types
____________________
- process of cell specialization
- Determines size, shape, metabolism, membrane, potential, & responsiveness to signals
- these types of cells are genetically identical, but different genes are turned on/off at specific times in development
Differentiation
____________________
- through gap junctions and desmosomes results in asymmetric cell divisions with different genes expressed in daughter cells
- affects gene expression in neighboring cells
- effect diminishes with distance
Juxtacrine signaling
____________________
- occurs at various developmental stages
- cell must detach from its original location and form a protrusion at the leading edge. This protrusion, called a lamellipodium, is formed by the polymerization of actin filaments. The cell then uses this protrusion to push itself forward, while the trailing edge of the cell contracts, pulling the cell forward.
- As the cell moves forward, it interacts with its environment through specialized proteins called integrins, which anchor the cell to the extracellular matrix. The cell also secretes enzymes called matrix metalloproteinases, which help to break down the extracellular matrix and create space for the cell to move through.
Ex : neutral crest cells migrate from neural tube to peripheral sites ——-> differentiate into distinct tissues
Cell migration
____________________
- differentiation of pluripotent stem cells is controlled by regulation of cell cycle, and activation or suppression of specific genes
Embryonic development
____________________
- changes in gene expression in 1 cell affect genes in another
- sets of regulatory genes direct development and differentiation
- growth factors (signaling proteins that cause inductive effects on competent cells)
- transcriptional factors (Hox genes are responsible for cephalization, segmentation
Induction
____________________
- regrowth of damaged tissue
- many differentiated cells cannot normally regenerate (muscle or nerve)
- liver, bone, & skin regenerate readily
Regeneration
____________________
- failure of normal cells to regenerate
- Eventually die
Cellular senescence
____________________
- programmed cell death due to cell damage
- part of normal fetal development & in the postbirth uterus
Apoptosis
____________________
- communication by electrochemical signals
- receives sensory info (sensory neurons) —–>
- processes info —–>
- relays response to muscles, glands, & effector cells
Nervous System
Neuron bundles form __________ nerves
Peripheral Nervous System (PNS)
Neurons & Glia form the networks of the _______________
Central Nervous System (CNS)
____________________
- combination of sensory & motor nerves
- contains Somatic Nervous System & Autonomic Nervous System
Peripheral Nervous System
____________________
- conscious sensation and movement
- includes reflexes
Somatic nervous system
____________________
- unconscious visceral senses such as detection of blood pressure or body temperature & unconscious movement
- heart contraction & peristalsis
Autonomic Nervous System
____________________
- brain/spinal cord processes, integrates, coordinates sensory info & responses
Central Nervous System
____________________
- transmit info to spinal cord/brain (CNS)
- afferent/inward
Sensory neurons
____________________
- transmit info from CNS to muscles/glands (effectors)
- efferent/outward
Motor neurons
Processing of information occurs in _____________ of CNS
Gray matter
- contains the cell bodies
- Appears gray because there is no sheath insulation like axons
_______________ transmits info between parts of brain or between CNS & PNS
White matter
- axons
The autonomic nervous system contains the ____________ & the ____________ .
Sympathetic nervous system and parasympathetic nervous system
____________________
- fight or flight sudden responses
Sympathetic nervous system
____________________
- rest and digest body functions
Parasympathetic nervous system
________________ Nervous System
- Controls digestive function
- Distinct from ANS
Enteric nervous system
____________________
- involuntary response to stimuli
- bypasses cognitive part of brain
- Stimulus info via afferent nerve to spinal cord gray matter (or midbrain for senses above neck) ——->
- Immediate response travels and efferent nerve to an effector
- Monosynaptic reflex arc (receptor—> sensory neuron—> motor neuron—> effector)
- Polysynaptic reflex arc (receptor—> sensory neuron—> CNS interneuron—> Motor neuron—> effector)
Reflex
3 structures of a neuron
__________
__________
__________
Soma (cell body containing nucleus & organelles)
Dendrites (receive stimulus)
Axon (long nerve fiber that branches/terminal buds at the end)
____________________
- part of axon at soma
- Lets signal pass, only if stimulus is sufficient
Axon hillock
____________________
- Gap between axon buds and next neuron
- Paracrine signaling conveys info
Synapse
____________________
- Signal initiated, propagated by opening ion channel —->
- Changes transmembrane electrochemical potential by letting certain ions in/out
Ion channels
____________________
- in dendrites
- Received chemical signal, open from outside
Ligand gated ion channels
____________________
- in the membrane of soma and axon
- Electrochemical signal
- Open from inside by voltage change
Voltage gated ion channels
____________________
- along axon, bulges of white fatty Lipoprotein secreted by certain glia
- Schwann in PNS
- Oligodendrocytes in CNS
Myelin sheath
(lipoprotein =myelin)
____________________
- myelinated nerve impulse is faster, because signal jumps between gaps in myelin
Saltatory propagation
____________________
- gaps between myelin
Nodes of Ranvier
__________ matter = unmyelinated
__________ matter = myelinated
Gray matter
White matter
____________________
- most abundant cells in nervous system
- Nourish, protect, & direct growth of neurons
- differentiate into 3 types : astrocytes, microglia, & ependymal cells
Glial cells
____________________
- glial cell that supports CNS neurons
Astrocytes
____________________
- glial cell that protects CNS from infection
Microglia
____________________
- glial cell that lines CNS cavities
Ependymal cells
____________________
- junction between 2 neurons or neuron & effector cell
Synapse
____________________
- cell conveys signal
- synapse
Presynaptic
____________________
- cell receives signal
- synapse
Postsynaptic
2 types of synapses are __________ & __________
Chemical synapse
Electrical synapse
____________________
- paracrine
- terminal buds of presynaptic axon, synaptic cleft filled with interstitial fluid, & a postsynaptic cell (neuron or effector)
- axon terminals contain vesicles filled with chemical neurotransmitters
- When an action potential arrives at terminal bud, the voltage gated calcium channels open —->
- neurotransmitters cross synapse & bind to postsynaptic cell receptors that trigger continued propagation of the signal —->
- neurotransmitters are digested by enzymes or absorbed by the presynaptic neuron
Chemical synapse
____________________
- juxtacrine
- nerve impulse is directly transmitted from one cell to the next via connexons (proteins channels at gap junctions between cells)
Electrical synapse
____________________
- voltage difference a Crossing Neuroal and Membrane when nerve not transmitting signal
- ATP energy to maintain
- Typically -70mV
- Inside membrane negative relative to outside
- is established by action of Na+/K+ pump
- ATP used to pump Na+ ions outside cell & K+ into cell (3:2 ratio Na:K)
Resting potential
____________________
- dendrites receive stimulus —-> alter membrane potential
- magnitude of change depends on strength of stimulus
Graded potential
____________________
- Na+ channels open, local membrane potential approaches 0 (depolarization)
- Strong enough signal at axon hillock triggers it —->
- Voltage gated Na+ channels, open in sequence down axon —->
- Followed by repolarization due to K+ voltage gated channels opening —->
- Resting potential reestablished by Na+/K+ pumps
Action potential
____________________
- takes ~2 milliseconds at any point on axon
- resting potential restoration (refractory period) takes 2-3 milliseconds more
Depolarization-Repolarization
Nerve impulses elicit either ____________ or ____________ responses in target cells
Excitatory response
Inhibitory response
____________________
- stimulus causes Na+ channels to open —->
- membrane depolarizes —->
- favors action potential, impulse propagation
Excitatory response
____________________
- stimulus opens K+ or Cl- channels —->
- Hyperpolarization —->
- inhibits action potential, prevents signal propagation
Inhibitory response
Many neurons are capable of both responses : in brain neurons, GABA finding elicits ____________ responses and Glutamate causes ____________ responses
Excitatory
Inhibitory
.
____________________
- is an all-or-nothing response (threshold) to the combination of excitatory & inhibitory responses at axon hillock
- intensity of stimulus does not affect voltage change of the action potential
- does increase impulses frequency
Nerve firing
____________________
- strength of a nerve signal can increase through multiple nerve impulses
- Spatial or Temporal
Summation
______________ summation
- many neurons at once
Spatial
_______________ summation
- repeated impulses
Temporal summation
Both spatial and temporal summation increase ____________ levels
Neurotransmitter
____________________
- contains somatic nervous system & autonomic nervous system
- 12 cranial nerve pairs (some sensory, motor, & mixed)
- 31 spinal pairs (mixed)
Peripheral nervous system
__________ of spinal nerves innervate skin, muscle, & viscera
Rami (branches)
________________ nervous system
- conscious sensation, voluntary movement, & reflexes
Somatic nervous system
________________ nervous system
- contains sympathetic nervous system & parasympathetic nervous system
- regulates unconscious functions
- sensory info from muscles/joints/organs
- controls smooth/cardiac muscle & glands
Autonomic nervous system
____________________
- neuronal clusters, get signals from CNS
- axons —-> effector
Autonomic ganglia
____________________
- fighter or flight response prepares for sudden activity, fear, or excitement
- increases heart rate, blood pressure, blood sugar, & breathing
- Dilate pupils
- Decrease blood flow to skin & digestive organs
- Norepinephrine is main neurotransmitter
Sympathetic nervous system
____________________
- rest and digest
- conserve energy, stimulate digestion/excretion, maintain heart rate, & anabolism
- Acetylcholine is main neurotransmitter
Parasympathetic nervous system
____________________
- consists of forebrain & brainstem
Brain
____________________
- consists of cerebrum, limbic system, & diencephalon
Forebrain
____________________ (part of brain?)
- consciousness
- Judgment
- Sensory processing
- Voluntary motor control
Cerebrum
____________________ (part of brain?)
- Primitive emotions
Limbic system
____________________ (part of brain?)
- Thalamus
- Hypothalamus
- Basal ganglia (information integration)
- Autonomic functions
Diencephalon
____________________
- consists of the midbrain, & hindbrain
Brainstem
_________________ (part of brain?)
- auditory & visual reflexes
- alertness & arousal
- crosses right brain to control left side of body & left brain to control right side of body
Midbrain
____________________ (part of brain?)
- includes pons
- nerve fibers between forebrain, spinal cord, & cerebellum
Hindbrain
____________________ (part of brain?)
- Upper part of spinal cord
- Information from diencephalon regulates autonomic functions
Medulla oblongata
____________________ (part of brain?)
- controls body position, muscle movement, & balance
Cerebellum
____________________
- inside vertebral column
- myelinated tracts of white matter surrounding gray matter
- afferent neurons enter dorsally & synapse with interneurons —->
- efferent motor neurons exiting ventrally
- conveys information to & from brain
Spinal cord
____________________
- largest part of brain
- divided into hemispheres
- sense & control opposite sides of body (contralateral)
- cerebral cortex (convoluted outer, gray matter, & divided into 4 lobes)
- white matter under cortex controls impulse transmission to & from the cortex
Cerebrum
_________________
- functions = voluntary movement, sensory processing, olfaction, language, communication, learning, memory, & association
Cerebral cortex functions
2 inner cerebral structures are the _______________ & _______________
Limbic system
Hippocampus
___________ System
- contains amygdala
- functions = autobiographical memory, social processing, & emotion
Limbic system
__________________ (part of brain?)
- functions = long-term memory, spatial memory, & navigation
Hippocampus
____________________
- contains the thalamus, basal ganglia, hypothalamus, & epithalamus (pineal gland)
Diencephalon
__________&__________
- route sensory info to the cerebral cortex
Thalamus & basal ganglia
____________________
- collects homeostatic sensory info & provides nervous & endocrine control of the pituitary
Hypothalamus
____________________
- connects limbic system to rest of brain, secretes melatonin, & controls circadian rhythms
Epithalamus (pineal gland)
____________________
- information to CNS about internal & external environments
- sensory receptors stimulate afferent neurons with excitatory or inhibitory graded potentials
- if stimulation is above threshold for depolarization (excitatory) or hyperpolarization (inhibitory) —->
- impulses propagate through peripheral nervous system to central nervous system
Senses
____________________
- exteroception
- touch, temperature, pain, pressure, taste, smell, site, hearing, balance, & motion
- sensory cells stimulate afferent nerves of somatic nervous system
External senses
____________________
- interoception
- blood sugar, salt, pH, CO2, blood pressure, long extension, gag, reflex, tendon/ligament proprioception, deep pressure, & pain
Internal physiological senses
____________________
- A major brain function is to integrate signals from different senses
- Ex : kinesthetic awareness is knowing body position by integrating multiple senses (motion sickness is a failure to integrate visual & balance senses)
Multisensory integration
____________________
- fluid filled spherical organ
- viscous aqueous humor fills the space between lens & cornea
- virtuous humor gel fills behind lens
- ciliary muscles attached to lens by suspensory ligaments & change lens shape to focus (accommodation)
Eye
The fibrous tunic (outer layer) forms the ________ & the _________.
Cornea
White sclera
The vascular tunic (middle layer) of the eye supplies nutrients/O2 two adjacent layers and forms the _______________ , _______________ , & _____________ .
Choroid
Ciliary muscle
Iris
____________________
- smooth muscle that forms the pupil
Iris
The nervous tunic (inner layer) of the eye forms the ____________ .
Retina
____________________
- contains photoreceptors (rods/cones)
- contains bipolar cells, horizontal cells, & amacrine cells
- contains optic nerve ganglionic cells
Retina
____________________
- concentrated along margins of retina
- detect low light without color
Rods
____________________
- concentrated in back of retina
- detect color
- when exposed to light, pigments reduce inhibitory neurotransmitters, which allows signals to propagate along optic nerve to brain (processed and visual cortex of occipital lobe)
- some neurons convey information to the midbrain to control iris & ciliary muscles
Cones
____________________
- contains auricle & auditory canal
- ending with the tympanum which vibrates in response to air vibrations (sounds)
External ear
____________________
- air filled, mucus lined chamber between tympanum & inner ear
- 3 tiny bones (ossicles) convey sound to oval window
Middle ear
What are the three tiny bones of the middle ear?
_____________
_____________
_____________
Maleus
Incus
Stapes
____________________
- vibrations, transmitted to fluid filled vestibule & cochlea —->
- inner hairs on cochlear organ of Corti vibrate with sound frequency —->
- convey signal to cochlear nerve
Inner ear
Auditory input travels from cochlear nerve to the ____________ through the ____________ to auditory cortex on the temporal lobe
Medulla
Thalamus
____________________
- hairs on the inner ear vestibule & semicircular canals detect head position & movement respectively —-> send a signal to cerebellum
- Integrated with proprioceptor & visual information in the cerebral cortex
Balance (equilibrium)
________ in skin detect pain & temperature
Nerves
_______________ sense hair motion
Follicle receptors
Cells in _____________ detect touch
Lower epidermis
Skin _______/________ detect deep pressure
Meissner/Pacinian corpuscles
____________ detect dissolved molecules in olfaction
Chemoreceptors
Thousands of distinct receptor proteins on olfactory receptor cells cilia trigger metabolic cascades when activated, which send signals to ______________ neurons, then send info to ______________ and _______________
Olfactory bulb neurons
Frontal lobe
Limbic system
Taste buds on _____________ contain taste cells
Tongue papillae
Food chemicals bind to receptor proteins, then neurotransmitters depolarize sensory neurons which send signals to the __________ & __________ .
Medulla
Thalamus
The 5 primary tastes are __________ , __________ , __________ , __________ , & __________ .
Sweet
Salty
Sour
Bitter
Umami (savory taste associated with Glutamate)
____________________
- chemicals released by presynaptic cells, trigger response to postsynaptic cells
- Include amino acids, peptides, purines, lipids, & inorganic gases such as CO & N2O
- Vary in location, duration, & type of elicited stimulus
Neurotransmitters
____________________
- specific to a particular neurotransmitter
- elicit either inhibitory responses or excitatory responses
Receptors
____________________
- opens ligand-gated channels or triggers complex mechanisms
Neurotransmitter/receptor binding
____________________ (neurotransmitter)
- neuromuscular junctions —-> muscle contraction
- Toxins prevent it’s breakdown (tetanus & strychnine)
Acetylcholine (ACh)
____________________ (neurotransmitter)
- brain —-> learning/memory & reward
Dopamine
____________________ (neurotransmitter)
- brain —-> alertness & arousal
Norepinephrine
____________________ (neurotransmitter)
- CNS—-> good mood, appetite, sleep, & learning/memory
Serotonin
____________________ (neurotransmitter)
- brain —-> learning/memory
Glutamate
____________________ (neurotransmitter)
- CNS —-> reduce pain, inhibit GABA & increase glutamate
- Natural opiate
Endorphins
____________________ (neurotransmitter)
- senses & brain —-> sleep (caffeine competes) & pain reception (sensory)
Adenosine
____________________ (neurotransmitter)
- brain —-> inhibitory
- alcohol binds to receptors
GABA
____________________
- Mental processing/thought
- Working memory, language, comprehension & production
- Calculation, reasoning, & decisions
- Conscious or unconscious
- Heredity & epigenetic neural development influence
Cognition
____________________
- awareness of cognitive/physical self & environment
- Multiple areas of CNS & sensory peripheral nerves
Consciousness
____________________
- knowledge, skills, & ideas
- Conscious or unconscious
- Involves sensation, memory, & habituation (conditioning)
Learning
____________________
- primary auditory, but also visual & physical (symbols for encoding & sharing information)
- Processing mostly regulated by Broca’s area / Wernicke’s area in frontal & temporal lobes
Language
____________________
- interaction of diaphragm, larynx, glottis, sinuses, tongue, mouth, teeth, & lips
Speech
____________________
- Encoding : receive, process, & integrate information
- Storage : glutamate mediated synaptic patterns record info in a retrievable form
- Retrieval : consciously or unconsciously retransmitting stored memory
Memory
3 types of memory are, _______________ , _______________ , & _______________ .
Sensory memory
Short term memory
Long-term memory
_____________ memory
- < 1s
- immediate recall
- no cognitive control
Sensory memory
_____________ memory
- < 1 min
- transient neuronal patterns
Short term memory
_____________ memory
- indefinite duration
- stable changes in synaptic connections, thresholds, & intensity among >100 billion neurons in many parts of the brain
Long term memory
Neural plasticity leads to __________________
Long term potentiation
____________________
- consolidates new memories
- key to storing/retrieving autobiographical memory (things you’ve done/had)
Hippocampus
___________& ___________
- Store working memory (language/sensory associations)
Frontal & Parietal lobes
____________________
- emotional memory
- Fear in dangerous situation
Amygdala
__________/__________
- Store motor skill memory
Basal ganglia / cerebellum
Emotional perception and response
- mostly in limbic system structures & many of which also process/store memory
- __________ : associates memory with emotional importance
- __________ : associate sensory stimuli with memories
- __________ : response to/affects homeostatic/endocrine/autonomic nervous responses to emotion (heart rate changes, temperature, blushing, adrenaline secretion)
- __________ : neurological source of judgment & anticipation of consequences & tempers emotional responses
Amygdala
Hippocampus
Hypothalamus
Prefrontal cortex
Stress
- physiological / psychological (or both)
- similar nervous & endocrine responses to both —-> stimulation of sympathetic nervous system
- __________ : processes emotion
- __________ : adjusts homeostasis (affects pituitary/adrenal function)
- __________ : problem-solving and planning
- __________ : mood regulation
Amygdala
Hypothalamus
Prefrontal cortex
Pons
____________________
- fail to distinguish reality for unreal perceptions
- delusion, hallucination, lack of emotion, impaired ability to communicate/form relationships
- linked to limbic system Dopamine overproduction (serotonin/glutamate possibly linked)
Schizophrenia
____________________
- mood disorder, low motivation, hopelessness, or sadness, low, self-esteem, irritability, fatigue, self-destructive behavior
- may be related to low activity of endorphins, serotonin, dopamine, & norepinephrine
Clinical depression
____________________
- Progressive incurable dementia
- Onset : short term, memory loss & neural plaques/tangles in brain
- Later : confusion & long term memory loss & social withdrawal
Alzheimer’s
____________________
- degenerative disease of CNS
- Onset : dopamine producing so decline in midbrain substantia nigra & causes muscle control loss & slow movement (shaking)
- Later : followed by dementia, depression, other neurological problems, and accumulation of æ-synuclein protein in neurons
Parkinson’s
____________________
- Chemical communication via blood
- Exerts control at cell, tissue, & organ level
- work together with nervous system to maintain homeostasis
- Positive feedback loops
- Negative feedback loops
Endocrine system
Endocrine glands or tissues secrete hormones by __________ & __________ directly into the bloodstream
Diffusion
Exocytosis
_____________ effects
- stimulate or inhibit growth
- Control reproductive cycle (development in puberty, pregnancy, birth, & menopause)
- induce apoptosis
- Regulate metabolism
- Maintain homeostasis
- Regulate immune physiological response to emergencies, stress, & arousal
Hormone effects
Production of ________________
- regulated by blood concentration of ions, nutrients, water, & pH (homeostasis)
- Nervous system signals (sensory & emotional control)
- Environment (light & temperature)
- Other hormones (developmental & positive or negative feedback)
Production of hormones
2 types of hormones : ____________ & ____________
Amino acid based (water soluble)
Steroid (lipid soluble)
____________________
- Single modified amino acids (serotonin, melatonin, histamine, epinephrine, & thyroxine)
- Short polypeptides (ADH, calcitonin, & TRH)
- Larger proteins (insulin, glucagon, & LH)
-Most are hydrophilic & transported dissolved in plasma
- Bind to surface proteins
- Most initiate a biochemical pathway that triggers intended cellular or molecular changes
Amino acid-based hormones
____________________
- sex hormones & adrenocorticoids
- Hydrophobic lipid derivatives that are transported in blood, bound to specific globulin proteins
- Lipid chemistry allows them to diffuse through the membrane into cell & nucleus (interact with receptors & act directly on gene expression)
Steroid hormones
____________________
- causes release of TSH
Thyrotropin releasing hormone (TRH)
____________________
- causes release of GH
Growth hormone releasing hormone (GHRH)
____________________
- causes release of FSH & LH
Gonadotropin releasing hormone (GnRH)
____________________
- causes release of ACTH
Corticotropin releasing hormone (CRH)
4 hormones of the Hypothalamus are
____________
____________
____________
____________
TRH
GHRH
GnRH
CRH
____________________
- causes release of T3 & T4
Thyroid stimulating hormone (TSH)
____________________
- causes release of corticosteroids
Adrenocorticotropic hormone (ACTH)
4 hormones of the Anterior Pituitary are
____________
____________
____________
____________
TSH
ACTH
FSH
LH
____________________
- hormones synthesized in Hypothalamus, but secreted from here
Posterior pituitary
2 hormones of the Posterior Pituitary are
____________
____________
ADH
GH
2 hormones of the Thyroid are
____________
____________
T3
T4
The hormone secreted by the Parathyroid is the ____________
PTH
The hormone secreted by the Duodenum is the ____________
CCK
____________________
- integrates CNS/endocrine function
- part of brain composed of nerve tissue
- autonomic sensory info (temperature, blood, osmolarity)
- affects appetite, thirst, sex drive, & emotions
- neurosecretory cells produce peptide hormone-releasing factors (TRH, GHRH, GnRH, & CRH) via hypophyseal portal capillaries directly to the Anterior Pituitary
- neurons to the Posterior Pituitary trigger release of ADH & Oxytocin
Hypothalamus
____________________
- under Hypothalamic neuroendocrine control
- 2 lobes
Pituitary gland
_______ to kidneys to reabsorb water if blood osmolarity is high
ADH
__________ affects smooth muscle contraction (birth & lactation)
Oxytocin
__________ hormones stimulate other glands
Tropic
____________________
- hormone that stimulates the adrenal cortex to release androgens & corticosteroids
ACTH
____________________
- hormone that stimulates the Thyroid to release T3 & T4
TSH
____________________
- hormone that stimulates the maturation of ovarian follicle (female) or maturation of sperm (male)
FSH
____________________
- hormone that stimulates ovulation & corpus luteum formation (female) or testosterone production (male)
LH
____________________
- direct acting hormone
- cell growth —-> liver produce growth factors—-> bone growth
GH
____________________
- milk production
Prolactin
____________________
- 2 lobes around trachea below larynx
- produces 3 hormones
Thyroid
__________& __________
- amino acid derivatives of Tyrosine (contains iodine)
- regulate basal metabolic rates
- increase rates of protein synthesis
- in children stimulate growth & nervous system development
T3 & T4
Which is more active, T3 or T4 ?
T3
____________________
- lowers blood Ca2+ concentration & increases deposition of calcium by osteoblasts
- decreases Ca2+ absorption by intestine
- decreases kidney reuptake of Ca2+
Calcitonin
____________________
- 4 small glands in dorsal surface of thyroid
- produce PTH
Parathyroid
____________________
- causes blood Ca2+ to increase
- activated by Vitamin D
- enhances kidney reabsorption of Ca2+
- enhances intestinal absorption
- increases osteoclasts activity (dissolve bone to raise blood Ca2+)
PTH
Calcitonin & PTH exemplify _____________ hormones
antagonistic
____________________
- endocrine & exocrine functions
- produce testosterone, responsible for sexual differentiation in embryonic development
- LH increases —-> testosterone production increases. —-> development of primary & secondary sex characteristics (body hair, increase muscle mass, & bone density)
Testes
_____________________
- produce estrogen & progesterone in response to increased LH
Ovaries
_____________________
- induce development of female secondary sex characteristics, the reproductive tract, & ovulation
- increase bone density, fat deposition, muscle mass, & blood clotting
- affects cholesterol, osmoregulation, thyroid function, & emotions
Estrogens
_____________________
- causes endometrium buildup before ovulation or pregnancy
- suppresses lactation in pregnancy
- reduces immune function (prevents miscarriage)
- inhibits labor
- strengthens myelin, collagen, skin, bone, teeth, ligaments, & thyroid function
Progesterone
After ovulation progesterone is produced by _______________
Corpus luteum
______________________
- above kidneys
- affect fight or flight response
- function of the sympathetic nervous system, metabolism, homeostasis, & development
Adrenal glands
______________________
- secretes corticosteroids
- mineralocorticoids (aldosterone) : water, Na+, & Cl- retention
- glucocorticoids (cortisol) : increase gluconeogenesis, blood sugar, & cell permeability
- gonadocorticoids (DHEA& estradiol) : sex development
Adrenal cortex
______________________
- secretes catecholamines
- Epinephrine/norepinephrine (adrenaline/noradrenaline) : fight or fight response —> constrict blood flow in organs/skin, & vasodilate flow to skeletal muscles, brain, & heart
Adrenal medulla
______________________
- islets of Langerhans secrete insulin —->
- causes glucose uptake from blood, increases cellular respiration, & promotes protein synthesis
- glucagon is antagonist —->
- response to low blood sugar causes liver glycogen hydrolysis & promotes gluconeogenesis from protein/fat
- somatostatin —-> inhibits insulin and glucagon
Pancreas
______________________
- secreted by pineal gland
- Affects sleep & circadian rhythm
Melatonin
______________________
- secreted by heart cells in atria when blood pressure or volume is high
- Antagonist to aldosterone
- Reduces water, Na+ , and fat in blood
Atrial natriuretic peptide (ANP)
_______________ hormones
- mostly hydrophilic
- variable/cyclical in short term
- Cannot diffuse through plasma membranes
- Synthesized in rough ER —->
- Transported to Golgi bodies —->
- Packaged in vacuoles —->
- Secreted by exocytosis —->
- Transported in blood to receptors on target cells
- (insulin, epinephrine, melatonin, CCK)
Peptide hormones
_______________ hormones
- hydrophobic (some amino acid hormones)
- exit directly through membrane
- Mostly insoluble in blood plasma
- Carried by hormonal specific globulin proteins in equilibrium with <1% of hormone free in the bloodstream
Steroid hormones
__________ hormone molecules can diffuse from capillaries into target cells (as they diffuse into cells, more bound hormones becomes free, maintaining constant blood concentration)
Free
Developmental or baseline metabolic hormones include _____ hormones, ____________, _____, & _____
Sex hormones
Corticosteroids
T3
T4
Hormones bind to receptor proteins & initiate a cellular response, where surface receptors are for __________ hormones & intracellular receptors for __________ hormones
Hydrophilic
Hydrophobic
True or false
Some receptors are hormone specific, others respond to several
Some cells have multiple receptors that bind to a single hormone
True
__________ hormones bind own receptors, disrupt antagonist/receptor binding
Antagonistic hormones
Hormone/receptor binding triggers certain _________________ pathways
- Phosphorylates or dephosphorylates certain molecules
- opens or closes channel proteins
- Starts Cascades that increased concentration of second messengers (cAMP)
- Activates intracellular communication mechanisms
Signal transduction pathways
_______________
- hormone/receptor complex is transported into a nucleus
- Interacts with specific gene promoter, inhibitor DNA sequences, or associated proteins
- Amplifies or suppresses expression of specific genes
Hydrophobic hormones
_______________
- Key role in maintaining stable, optimal internal conditions
- Body temperature, blood solute concentration, & blood pressure
Homeostasis
_______________ feedback control
- the products of hormone function trigger inhibition of production or activity of the hormone
- hormone function —> products —> inhibition of hormone function
Negative feedback control
_______________
- hormones with opposing affects
- Ex : calcitonin (decrease blood Ca2+) & PTH (increase blood Ca2+)
Antagonistic hormones
True or false
Homeostatic control is often more complex
EX : blood sugar balance is affected by insulin, glucagon, somatostatin, Gastrin, epinephrine, norepinephrine, ACTH, and glucocorticoids
True
_______________ diseases
- over or under production of hormones due to diet, environment, tumors, lesions, or genetic problems
- Linked to production of hormones, receptor proteins, or feedback mechanisms
Endocrine diseases
_______________
- most common endocrine disorder
- Disrupted function of insulin in response to elevated blood sugar
- Alters glucose metabolism
- Sugar builds up in blood —> kidneys filter excess sugar —> water imbalance as urine becomes hypertonic —> excessive urination, thirst, fatigue, headaches, & blurred vision
- Unchecked causes : acute ketoacidosis (ketone bodies), heart, disease, blood pressure, circulatory problems, kidney damage, & stroke
- Type 1 : insulin deficiency
- Type 2 : insulin receptor or uptake problems
Diabetes mellitus
_______________
- secreted by duodenum when chime exits stomach
- Triggers the release of pancreatic enzymes & bile
- Similar is Gastrin from stomach parietal cells
Cck
_______________
- secreted by adipose cells
- Decreases appetite & increases metabolism
Leptin
_______________
- secreted by seminal vesicles/other tissues
- Vasodilation, bronchoconstriction, & smooth muscle control
Prostaglandins
_______________
- secreted by seminal vesicles/other tissues
- Vasodilation, bronchoconstriction, & smooth muscle control
Prostaglandins
_______________
- secreted by liver
- Vasoconstriction
- Causes aldosterone released by the adrenal cortex
Angiotensin
_______________
- secreted by kidney
- Stimulates angiotensin production
Renin
_______________
- secreted by kidney
- A growth factor that stimulates erythrocyte production
Erythropoietin (EPO)
____________ receives autonomic sensory homeostatic information
- Respond with neurons at end in the posterior pituitary or with hormone secretion to hypophyseal portal capillaries
Hypothalamus
_______________
- develops from embryonic nerve tissue
- Fight or flight secretions excite sympathetic/inhibit parasympathetic function
- Act as neurotransmitters & as hormones on other target organs
Adrenal medulla
_______________
- response to nursing
- Sensory cells and nipple signal Hypothalamus to release oxytocin from posterior pituitary
- Milk released by mammary glands
Lactation
_______________ responses
- hormones can affect stress, fear, aggression, arousal, & hunger
Emotional
True or false
Hormones influence behavior but behavior affects hormone levels
(correlation between hormones & behavior/emotion)
True
Increased _______________ —> increases aggression, sexual arousal, & antisocial behavior
Testosterone
_______________
- diurnal shifts in melatonin
- Menstrual cycle
- Pregnancy
- Postpartum
- Menopausal changes
Normal hormone fluctuations
True or false
Abnormal hormone levels affect behavior
True
True or false
The triggering of behavior directly by the nervous system without mediation of hormones is much faster than hormone mediated behavior
True
____________ extend from olfactory bulb into sinuses
Olfactory dendrites
_______________
- throat
- connects sinuses, mouth, auditory tubes, trachea, & esophagus
Pharynx
_______________
- A flap blocking glottis when swallowing
Epiglottis
_______________
- rings of cartilage (don’t have back part)
- connects pharynx to lungs
- lined with cilia (push mucus + particles up to the pharynx & sinuses)
Trachea
_______________
- top of trachea
- Contains vocal cords
Larynx
_______________
- spongy, elastic, high surface area organs
- Gas exchange between air & blood
Lungs
_______________
- branch from trachea to bronchioles, and lead to alveoli
- lined with cilia
Bronchi
_______________
- clusters of expandable air sacs around bronchioles
- Surrounded by capillaries
Alveoli
_______________
- muscle separating abdominal & thoracic cavity
- Causes breathing
Diaphragm
_______________
- primary respiratory function
- Pulmonary capillaries surround alveoli
- Diffusion occurs between alveolar air gases & gases dissolved in blood
Gas exchange
_______________
- lower partial pressure than inhaled air —>
- O2 diffuses into blood —>
- RBC Hemoglobin binds up O2 —>
- Lowers O2 partial pressure so more diffuses in
Pulmonary blood O2
_______________
- higher partial pressure than air —>
- CO2 diffuses into alveoli
Pulmonary blood CO2
_______________
- In non-sweating animals, evaporative cooling occurs via water vapor loss from respiratory system
Thermoregulation
Physical barriers to infection are an __________ immune response to infection (mucous membranes trap particles)
Innate
_______________
- found in the lungs, bronchi, trachea, and sinuses
- Bring particles to pharynx to be eliminated
Cilia
_______________
- antibody from mucous cells
- binds/inactivates pathogens
- Adaptive immunity
IgA
Gas exchange happens in the lungs through the diffusion between ____________ & ____________
Alveoli
Capillaries
Lungs:
(Huge or small) surface area
(Thick or thin) membrane between alveoli
(rapid or slow) diffusion in capillaries
Huge
Thin
Rapid
Alveolar cells secrete _____________ which prevents collapse & lowers water surface tension (facilitating diffusion)
Surfactant
Diffusion of O2 follows concentration gradient into the bloodstream
- Inhaled alveolar air
- Diffusion across surfactant layer
- Diffusion across alveolar epithelial layers, & adjacent capillary endothelium
- diffusion/dissolution into blood plasma
- Diffusion into RBCs & cooperative binding of __#__ O2 molecules to the iron atoms in __#__ heme moieties of hemoglobin
4
4
_______________
- striated muscle that is posterior to lungs & anterior to liver
- controlled by the phrenic nerve
- Voluntary signal originates in Cerebral Cortex
- Involuntary signal originates in Medulla Oblongata
- intercostal muscles between ribs help
Diaphragm
Muscle contraction & relaxation of the _____________ cause change in lung volume, change in pressure gradient, & causes breathing
Diaphragm
Lung inhalation is caused by a ____________ diaphragm
- Flattens & increases thoracic cavity volume which generates negative pulmonary air pressure (draws air into lungs to fill volume)
Contracted
Lung exhalation is caused by a ____________ diaphragm
- Dome shaped & reduces volume of thoracic cavity which allows elastic resiliency of lungs & intercostal muscles to squeeze air out
Relaxed
_______________
- volume of air into and out of the lungs with each normal involuntary breath
Tidal volume
Vt
The lung is surrounded by 2 membranous __________ with a fluid filled cavity in between
Pleura
Intrapleural pressure is (higher or lower) than the alveolar pressure?
Lower
_________________ = alveolar lung pressure - intrapleural pressure
(always >0 which keeps lungs inflated)
Transpulmonary pressure
Ptp
Alveolar lung pressure is equal to ________________ pressure
Atmospheric
Alveolar lung pressure (Ppul)
True or false
The pleural cavity of each lung is separate
True
_______________
- if one of the pleura is perforated in the lungs
- P tp = 0
- The lung will collapse
Pneumothorax
_______________
- reserve volume
- Even when exhaling forcibly (there always remains about 2 L of air)
Residual air
_______________
- Low surface tension inside of alveoli prevents lung tissue from adhering which allows for re-inflation against the collapsing force of resiliency
Surfactant
_______________ Law
- diffusion & solubility of gas in liquid is proportional to partial pressure of that gas in air adjacent to the liquid
- explains normal exchange of gases between blood - alveoli
- also explains “ the bends” and deep diving
Henry’s law
____________________
- O2 bound to hemoglobin heme groups in RBCs
- Transports O2 from lungs
- sigmoid curve of pO2 effect on the hemoglobin oxygenation shows cooperativity at low O2 (exponential increase)
- leveling effect of saturation of hemoglobin at high O2
Oxyhemoglobin
Oxygen released by hemoglobin, increases with ____________ , ____________ , & _____________
Increased CO2 (cause decreased pH - “ the Bohr effect”)
DPG (product of glycolysis, which is elevated with energy demand)
Temperature (associated with energy demand & exercise)
____________________
- catalyzes CO2 to HCO3- for blood transport from tissues to lungs
Carbonic anhydrase
Rate of ____________
- involuntary control by medulla oblongata neurons send signals through phrenic nerve to diaphragm
- voluntarily influenced by cerebral motor cortex
Ventilation
Acid chemoreceptors in _______/__________ can override voluntary control of rate of ventilation
Aorta/Hypothalamus
If blood pCO2 concentrations increase the pH decreases & the detection by acid-sensitive chemoreceptors forces the ____________ to trigger inhalation
Medulla
(hyperventilation—> drop in blood CO2—> medulla slows breathing rate)
_______________ Nervous System causes bronchodilation which opens airways & allows more air exchange
Sympathetic
_______________ Nervous System causes bronchoconstriction which limits air exchange (immune response to perceived harmful substances, such as allergens or toxins)
Parasympathetic nervous system
____________________
- Muscle that pressurizes blood for efficient flow to tissues for exchange & renal filtration
Heart
Blood vessels that carry blood towards the heart are ____________
Veins
Blood vessels that carry blood away from the heart are ____________
Arteries
_______________ circulation
- pulmonary arteries take deoxygenated blood from heart to lungs
- Branch to alveolar capillaries
- Returns oxygenated blood to the heart via pulmonary veins
Pulmonary circulation
________________ circulation
- Circuit of arteries from left side of heart
- Capillaries and tissues throughout the body
- Then to the veins
- Returns deoxygenated blood to right side heart
Systemic circulation
____________________
- A tissue that is predominantly liquid
- Carries, dissolved, nutrients, wastes, & biochemical secretions throughout the body
- The cells serve many functions such as transport (O2/CO2), protection (immune), & repair (damaged tissues or organs)
Blood
Circulatory cells include ____________ , ____________ , & ____________
Erythrocytes
Leukocytes
Platelets
Nutrients are absorbed from intestines & transported first to the _________, then circulated throughout the body
Liver
The circulatory systems internal biochemicals include __________ & __________ which are secreted from source cells/glands to target tissues
Hormones
Antibodies
The circulatory system transports metabolic wastes such as urea, excess minerals, & water to the __________ where it is filtered and excreted
Kidneys
Superficial blood vessels dilate to get rid of excess __________ & constrict to conserve
Heat
The heart is CNS controlled by the _______________ (modified by sympathetic & parasympathetic systems)
Medulla oblongata
The SA node is found in the ______________ wall
Right atrium
Heart neuromuscular tissue ask as pacemaker and causes atria to contract —> send signal to AV node/bundle of His/Purkinje fibers which ________ ventricular contraction until ventricles are full
Delay
____________________
- exerted by blood on arterial walls
- Maximum (systolic) to minimum (diastolic)
- 120/80 is normal
- 140/90 is hypertension
Blood pressure
Blood flows from arteries to arterioles to capillaries & blood pressure (drops or rises) due to blood viscosity & friction from increased surface area of capillary walls
Drops
True or false
In the capillaries the drop in velocity facilitates efficient nutrient, gas, & waste exchange
True
Blood pressure can be affected by
________________
________________
________________
________________
________________
________________
Action of venous valves
Gravity against vertical flow
Muscle movement/breathing
Vasoconstriction or dilation
Blood volume
Blood viscosity
____________________
- High pressure in arteries & renal arterioles
- Low pressure in large veins & atria
- trigger negative feedback barrow reflex in medulla (maintain constant BP)
- affect Renin & Angiotensin secretion by kidney
- Raises BP by vasoconstriction in response to low blood volume or high osmolarity
Blood pressure regulation
________________________
blood vessels form loops between heart & lungs and other tissues
Closed circulating system
________________________
thick walled muscular vessels that carry high pressure blood away from heart & blood pressure drops as system branches
Arterial circulation
________________________
- thin porous walls (microscopically narrow) in which RBCs line up singly to pass through
- form link between arterioles and venules (except for portal systems)
- single endothelium layer
Capillary beds
________________________
- thin & not muscular
- low pressure
- skeletal muscle activity aids in flow
- presence of valves
Venous circulation
________________________
- arterioles lead to 2 capillary beds in sequence rather than directly from capillaries to venules
Portal systems
________________________
- due to thin capillary walls, hydrostatic pressure, osmotic pressure, & vasodilation
Capillary permeability
___________________ portal system
- capillary bed from hypothalamus to anterior pituitary
Hypophyseal portal system
_________________ portal system
- capillaries in the /small intestine villi carry blood via portal vein to liver capillaries
- enzymes remove toxins & regulate blood sugar
Hepatic portal system
_________________ portal system
- in each nephron
- blood filters via glomerular capillaries into Bowman’s capsule then blood flows to capillary vasa recta where nutrients, water, & ions are reabsorbed back from convoluted tubule and loop of Henle
Renal portal system
Blood -> _____% plasma & _____% 45% cellular components
55% plasma
45% cellular components
_______________
- water, ions, gases, nutrients, hormones, proteins (albumin, immunoglobulins, fibrinogen, bilirubin), & wastes
Plasma
_______________
- produced from hematopoietic stem cells in bone marrow (fetal spleens)
- mature lack nucleus & mitochondria
- biconcave disks (high surface area)
- filled with hemoglobin
- live ~ 3 months
RBCs
_______________
- produced by bone marrow hematopoietic cells
- immune system cells (Neutrophils, Lymphocytes, Monocytes, Eosinophils, Basophils)
WBCs
_______________
- fragments of megakaryocytes
- help in clotting along with proteins (fibrin & collagen)
Platelets
_______________
- open circulatory system of vessels, organs, & tissues
- primary repository for immune system targeted function
- contains most of the WBCs
Lymphatic system
_______________
- production of immune cells (macrophages, dendritic, T cells & B cells)
Bone Marrow
_______________
- T cell maturation site
- secretes hormone Thymosin (stimulates immune system development in juveniles)
Thymus
_______________
- largest lymphoid tissue organ
- stores & activates immune cells
Spleen
_______________
- similar function as spleen
- dispersed throughout the body & some specifically associated with digestive, respiratory, & integumentary systems
Lymph Nodes
_______________
- transport lymph from lymphatic capillaries through vessels to thoracic duct (recycles lymphatic fluid into the blood)
Lymphatic vessels
_______________
- lymphatic capillaries in villi of small intestine & around colon
Lacteals
Recovery of lost fluid in capillary filtration of blood
- ____% of fluid lost through afferent capillaries is recovered by efferent capillaries
- ____% remains flowing interstitially
99%
1%
_______________
- collected in lymphatic vessels by pressure gradient
- muscular activity & valves aid in flow to thoracic duct then to subclavian veins
Interstitial fluid
Absorption of __________
- lacteals are responsible for most lipid absorption
- transported to bloodstream or deposited in adipose tissue
Lipids
_______________
- lymphocyte T and B cell production
- T cell maturation
Thymus & bone marrow
_______________
- T cell and B cell storage & proliferation
- B cell antibody production (cause of infection)
Lymph nodes, spleen, & tonsils
Lymphocytes receive antigens of infectious agents from the __________ cells
dendritic cells
_______________
- skin & epithelial layer (blocks infections and limit pathogens)
- sweat & sebum ( acidic and antimicrobial)
- stomach acid (kills pathogens)
- antimicrobial tears (protect cornea)
Physical Barriers
Nonspecific phagocytes are __________ & __________ (patrol blood & tissues to engulf pathogens or infected cells)
Neutrophils and Macrophages
__________ cells cause apoptosis in infected cells
Natural killer cells
__________ proteins secreted by infected cells cause cascade of immune responses
Interferon proteins
__________ proteins from the Liver stimulate immune responses and attract & enhance phagocytes
Complement proteins
__________ cells and _________ cause inflammation which allow phagocytes, immune proteins, and repair cells to enter injured areas
Mast cells and Basophils
_______________
- attraction of immune cells to chemicals secreted by infected cells
Chemotaxis
_______________
- hypothalamus causes this increase in temperature
- inhibits microbial growth and accelerates immune response
Fever
_______________
- specific defenses that recognize antigens of pathogens
- cells remain after infection to remember pathogens (respond quicker next time)
Adaptive immune system
_______________
- newborns have no immunity
- milk delivers IgA antibodies but more effective immune system
Passive Immunity
Active Immunity has 2 levels -> _____ & _____
Cellular and Humoral
_______________
- defense against infection in tissues
- antigen-presenting cells (APCs) detect infection then show antigens to T cells which cause the T cells to proliferate and then destroy infected cells (memory T cells remain after infection for the next time)
Cellular active immunity
_______________
- bind foreign antigen to antibodies on B cells then secrete antibodies against specific antigen (memory B cells remain after)
Humoral Active Immunity
_______________
- phagocytes to bacteria, fungi, and viruses
Neutrophils
_______________
- cytotoxic, degrade toxins, attack parasites, and cause inflammation
Eosinophils
_______________
- release Histamine in blood
- sensitive to parasites or allergen
Basophils
_______________
- release histamine in response to injury, complement protein, or IgE from infection or allergen
- found in connective tissue near skin and mucous membranes
Mast Cells
_______________
- develop into dendritic cells and macrophages
Monocytes
_______________
- antigen presenting cells (APCs)
- migrate to and reside in different tissues
- after activated they travel to lymph nodes and activate T cells
Dendritic Cells
_______________
- patrol bloodstream and tissues
- phagocytic and antigen presenting
Macrophages
_______________
- B cells and T cells
- B cells from Bone marrow
- T cells from Thymus
Lymphocytes
_______________
- APCs present antigens to inactive T cells then T cell clonal selection then proliferation of effector & memory T cells with receptor antibodies specific to the antigen presented
T cell activation
4 classes of effector T cells
____________
____________
____________
____________
Cytotoxic T cells
Helper T cells
Supressor T cells (regulatory T cells)
Natural Killer T Cells
_______________
- encounters a virus, fungus, or cancer cell with antigens corresponding to its receptor antibodies
- binds to and kills pathogen with Perforins (damage membrane) and Granzymes (destroy proteins)
- travels blood & lymph
Cytotoxic T cells
_______________
- activate T cells and B cells
- secrete lymphokines and interleukins
Helper T cells
_______________
- use Negative Feedback to turn off cell-mediated immune response after infection has been eliminated to prevent autoimmune responses
Supressor T cells
_______________
- combine functions like Helper T cells and Cytotoxic T cells
Natural Killer T cells
_______________
- B cells produce antibodies (Immunoglobulins or Ig)
- Ig binds to viruses, bacteria, and toxins (inactivate and target them for destruction)
Humoral Immunity
_______________
- proteins or polysaccharides on the surface of bacteria, viruses, tissue grafts, allergens
- elicit responses
Antigens
_______________
- proteins with specific antigen-binding sites
- composed of 5 polypeptide chains in a Y shape with variable antigen-binding sites
- stimulate complement system
Antibodies
5 types of immunoglobulins
__________
__________
__________
__________
__________
IgG
IgA
IgM
IgE
IgD
“GAMED”
Immunoglobulins _____ & _____ protect against blood/lymph pathogens and activate complement system
IgM and IgG
Immunoglobulin _____ protects against pathogen entry in mucous membranes
IgA
Immunoglobulins _____ & _____ act as antigen receptors on B cells
IgD and IgM
Immunoglobulin _____ binds to mast cells & basophils to release histamine (inflammation/Allergies)
IgE
_______________
- after specific antigen exposure the B cells make antigen-specific antibodies then clone themselves (plasma cells and some memory cells)
B lymphocyte clonal selection
_______________
- self cell antigens recognized by immune cells are ignored
- no 2 people have the same MHC (except identical twins)
MHC
major histocompatibility complex
Nonself cells lack matching ______ markers
MHC
____________ system functions
- intake essential nutrients, food, and water
- catabolize complex biochemicals into simple monomers (depolymerization and hydrolysis)
- absorption into bloodstream for use throughout body
- excretion of indigestible material
Digestive
4 steps of digestive system
____________
____________
____________
____________
Ingestion
Digestion
Absorption
Excretion
_______________
- breaks down large pieces into smaller ones
- increases surface are of food particles for more enzymatic molecule action
Mechanical digestion
_______________
- enzymes break down molecules
- amylase breaks down starch to maltose
- lipase hydrolyzes lipids into fatty acids & glycerol
Chemical digestion
(enzymatic)
Stomach pH is about ______ pH
2 pH
_______________
- folds in flexible stomach wall when empty
- allow expansion up to 2 liters
Rugae
_______________
- strong muscular rings
sphincters
Stomach 4 special cell types
____________
____________
____________
____________
Chief cells (zymogenic)
Parietal cells (oxyntic)
Mucous cells
Enteroendocrine
_______________
- secrete pepsinogen which is then activated by HCl to form pepsin (protease)
Chief Cells
_______________
- secrete HCl
- acidify by pumping protons/Cl- into stomach cavity
Parietal cells
_______________
- secrete much mucus to prevent damage to stomach lining by acid and protease enzymes
Mucous cells
_______________
- release gastrin and CCK into bloodstream (stimulates secretions of digestive enzymes when stomach receives food
- influences feeling hungry
Enteroendocrine cells
__________ digestive function
- secretes bile salts (emulsifies lipids so lipase enzymes can hydrolyze the smaller lipids)
Liver
_______________
- Liver stores glycogen
Glycogenesis
_______________
- hydrolysis of glycogen
Glycogenolysis
_______________
- Liver makes glucose from lipids/amino acids
Gluconeogenesis
_________ circulating function
- disposes dead RBCs
- produces blood proteins (albumin & clotting factors)
- synthesizes amino acids & stores vitamins
- coverts ammonia to urea for excretion
- breaks down toxins
Liver
Pancreas secretes __________ to neutralize chyme & activate zymogens
NaHCO3
Sodium bicarbonate
_______________
- internal small intestine surface covered with finger like projections (each covered with smaller projections)
- maximizes digestive & absorptive surface area
Villi & microvilli
_______________
- 1st section of small intestine
- most digestion occurs here
- stomach squeezes chyme through pyloric sphincter then pancreatic enzymes are secreted through ducts
Duodenum
_______ & ________
- majority of absorptive area
- amino acids, sugars, minerals, & water absorbed directly into mesentery capillaries to hepatic portal vein to liver
- epithelial cells absorbed fats (form lipoprotein chylomicrons) then transfer to lymphatic lacteals
Jejunum & Ileum
_______________
- cecum, appendix, ascending colon, transverse colon, descending colon, rectum, anus
Large intestine
_______________
- outer letter of kidney
- where filtration of blood occurs into the nephrons
Renal cortex
_______________
- layer of kidney that forms renal pyramids
- contains 2nd set of capillaries that recover nutrients & minerals
Renal Medulla
_______________
- collects urine before it flows to bladder
Renal pelvis
_______________
- functional unit of the kidney
- About 1 million per kidney
Nephron
_______________
- tight ball of capillaries
- receives high pressure blood from afferent arterial
- releases remaining blood into efferent arterial to vasa recta
Glomerulus
_______________
- spiracle chamber surrounding the glomerulus
- sends filtrate to proximal convoluted tubule
Bowmans capsule
_______________
- re-absorbs, nutrients, minerals, water into 2nd set of capillaries (vasa recta)
- Blood components reabsorbed or wastes removed in 3 sections
Convoluted tubule’s
Is the loop of Henle convoluted?
No
_______________
- The capillaries surrounding the convoluted, tubule‘s and loop of Henle
- flow to renal vein
Vasa recta
_______________
- drains filtrate from each nephron into the renal pelvis
Collecting duct
_______________
- Ultrafiltrate from pressure of blood entering these permeable capillaries and forced into Bowman’s Capsule
Glomerulus
_______________
- filtrate from Bowmans capsule moves through
- water, glucose, amino acids, and ions reabsorbed by vasa recta
Proximal convoluted tubule
_______________
- extension of the tubule into renal medulla
- 1st part reabsorbs water into interstitial fluid
- 2nd part is impermeable to water & pumps Na+ into interstitial fluid which helps maintain gradient for absorbing water in 1st part
Loop of Henle
_______________
- Endocrine controlled
- Active transport recovers filtered Ca2+ & secretes PO4^3- due to PTH
- Aldosterone causes Na+ recovery & loss of K+
Distal convoluted tubule
_______________
- Nephrons merge into collecting ducts
- Adjust permeability to water in response to changes in ADH, ANP, & aldosterone concentrations
Collecting Duct
When there is low blood osmolarity, osmosensors cause secretion of ____________ (travels to DCT where Na/K pumps excrete K & reabsorb Na/Cl and water) and cause secretion of ____________ (increases water reabsorption from collecting ducts)
Aldosterone
ADH
True or false : angiotensin stimulates aldosterone and has similar effects
True
Parathyroid hormone increases blood _____________
Ca2+
If high blood volume/pressure and low salinity then ____________ raises filtrate volume by preventing Na+ reabsorption
Atrial Natriuretic Hormone (ANH)
Baroreceptors for high pressure are found in __________ & __________
Aorta
Juxtaglomerular apparatus in kidney
Baroreceptors for low pressure are found in __________ & __________
Atria
Venae Cavae
______ BP caused by low blood volume, vasodilation, or low viscosity causes release of renin by kidney, activates liver to convert angiotensinogen to angiotensin, increases sympathetic nervous system, increases secretion of aldosterone and ADH, and increases vasoconstriction
Low
_______ BP reduces renin secretion, reduces ATH & aldosterone secretion, stimulates parasympathetic nervous system, increases vasodilation, and increases ANH secretion by atrial neurosecretory cells
High
The __________ main function is to lower the temperature for a sperm development
Scrotum
_______________
- coiled inside testes
- Site of sperm formation
Seminiferous tubules
____________ cells help support developing sperm
Sertoli cells
____________ cells secrete testosterone (causes sperm formation and puberty)
Leydig cells
_______________
- smooth muscled ducts on surface of testes
- Site of sperm maturation & storage
Epididymis
_______________
- smooth muscle ducts from testes into abdominal cavity
- Merge into ejaculatory duct through prostate gland into urethra inferior to urinary bladder
Vas deferens
_______________
- secrete components of semen (alkaline fluid in which sperm are ejaculated with nutrients, enzymes, & prostaglandins)
Seminal vesicles & Bulbourethral/prostate gland
_______________
- Common outlet for Reproductive and urinary tract
Urethra
_______________
- male genital (copulatory organ)
- Paired corpus cavernosae along dorsal side of penis filled with blood causing erection
Penis
_______________
- produce ova & hormones regulating development/reproduction
Ovaries
_______________
- clusters of cells with oocyte in center
- Some follicles stimulated temperature each month
- One ovary releases ovum then maturing follicle secretes estradiol then pituitary spike in LH then causes ovulation and ruptured follicle to become corpus luteum then secretes progesterone and estrogen to stimulate endometrial growth
Ovarian follicles
_______________
- fimbrae at distal end of uterine tubes guide ovum into oviduct then cilia propel ovum to uterus
Uterine tubes
_______________
- muscular elastic organ in which fetus develops
- Inner lining (endometrium) thickens each month anticipating implantation then lining shed if no pregnancy occurs
Uterus
_______________
- narrow posterior channel from uterus to vagina
Cervix
_______________
- mucus channel from vulva to cervix
- Receives sperm, passes menstrual fluid, and is birth canal
Vagina
Sperm formation
Spermatogonia proliferate on margins of seminiferous tubules & at puberty FSH & LH secretion increases by AP
_______ triggers, testosterone secretion, then secondary sex characteristics and mitosis of Spermatogonia into primary spermatocytes then which migrate to lumen of tubules, then undergo meiosis 1 then form 1n secondary spermatocytes, then undergo meiosis 2 then form for spermatids per germ cell
______ causes sperm to mature and grow flagella in the epididymis
LH
FSH
_______________
- secreted by Sertoli cells and testes when sperm count is high
- it decreases production of LH and FSH
- If there is a low sperm count, then its production stops, which let LH and FSH levels to rise
inhibin
_______________
- body and facial hair, lots of scalp hair, enlargement of larynx, deepening of voice, increased height, increased bone in muscle mass, widening of shoulders, increased sweat and oil secretions by skin
Secondary sex characteristics
Ovarian reproductive cycle (Average: 28 days) (Range: 21-35 days)
_______________ (1-14 day)
- FSH causes several follicles to mature then estradiol levels rise then suppress LH (various hormonal signals cause one follicle to develop ovum)
_______________ (14 day)
- Rising estrogen levels, then LH spike so follicle releases mature ovum, which is swept by cilia down ovarian tube and lives ~ 1 day in fallopian tube, then disintegrates
_______________ (14-28 day)
- LH spike at ovulation changes follicle to corpus luteum then secretes, progesterone and endometrial buildup and FSH & LH suppression
- Absent fertilization causes corpus luteum to dissolve and menstruation begins as endometrium breaks down
Follicular phase
Ovulation
Luteal phase
_______________ (~12 yrs old)
- 1st reproductive cycle begins as a Hypothalamic GnRH causes FSH & LH production by anterior pituitary, then increases progesterone/estrogen
Menarche
3 phases of uterine reproductive cycle
_______________
_______________
_______________
Menses (1-7 day)
Proliferative phase (7-14 day)
Secretory phase (14-28 day)
_______________
- discharge of tissue, mucus, blood from breakdown of endometrial tissue built up in uterus over previous 2 weeks
- Indicates no pregnancy
Menses
_______________
- FSH causes ovarian follicles to grow, secreting estradiol and estrogen
- promote formation of a new endometrial wall in the uterus
Proliferative phase
Menses and proliferative phase is coincide with _______________ phase
Ovarian follicular phase
_______________
- spike in LH & FSH then increase progesterone at ovulation
- Triggers rapid thickening and increased blood flow into uterine endometrium in preparation for implantation of a blastocyst
Secretory phase
The secretory phase coincides with the __________ phase in the ovarian cycle
luteal phase
After fertilization, the zygote moves through the uterine tube at _______ days
6-7 days
_______________
- reaches uterus as blastocyst
- Attaches to endometrium and erodes uterine capillaries, then get surrounded by maternal capillaries
- Secretes hCG (human chorionic gonadotropin)
- Keeps corpus latuem producing estrogen and progesterone
- Maintains uterine lining and prevents menstruation or ovulation
Implantation
_______________
- part of blastocyst forms Chorion with villi, with maternal/fetal capillaries in uterine wall
- Forms placenta, where nutrients/waste exchange between mother & fetus
Placentation
Embryonic ___________ forms, umbilical cord from placenta to fetus
- >9 weeks placenta, secretes, progesterone/estrogen (other placental hormones are immunosuppressive)
Allantois
_______________
- progesterone/estrogen increase until birth
- Promote fetal growth, memory development, & prevent labor
- After ~ 40 weeks the pituitary releases oxytocin, which causes labor contractions, prostaglandins to soften cervix, and lactation
Parturition
________________
- transverse light & dark bands due to sarcomere protein pattern
- long striated fibers, multinucleated, bundled to form a muscle
Skeletal muscle (voluntary & striated)
________________
- movement of hollow organs
- 2 layers (longitudinal - shortening/dilation) (circular - elongation/constriction)
Smooth muscle (involuntary & nonstriated)
________________
- branching cells connected via gap junctions/desmosomes that propagate signals rapidly for uniform contraction
- uninucleated
Cardiac muscle (involuntary & striated)
Sarcolemma is covered with invaginations called ____________ that carries membrane depolarization into the muscle fiber
T tubules
________________
- along muscle fiber like wires (thousands of repeating sarcomeres)
Myofibrils
________________
- modified ER surrounds each myofibril & adjacent to T tubules
- contain Ca2+ needed to convey action potential to sarcomeres
Sarcoplasmic reticulum
________________
- arrangement of cytoskeleton proteins
- facilitates contraction
Sarcomere
________________
- only in heart
- single nucleus & each with T tubules
- gap junctions & desmosomes form intercalated disks to transmit signal from SA Node to AV Node (arterial cells contract together then ventricular cells contract)
Cardiac muscle cells
_______________
- spindle shaped cells, arranged in sheets or layers
- I moved with gradual sustained contraction simultaneous movement in all fibers of a muscle
Smooth muscle
_______________
- lack sarcomeres, sarcoplasmic reticulum, or T tubules
- actin & myosin filaments spiral within the cell
- contain calmodulin, triggers contraction when Ca2+ binds to it
Smooth muscle cells
Smooth muscle contraction is triggered by ______________ neurons
Autonomic
2 key contractile proteins in sarcomeres are __________ (thick filaments) and __________ (thin filaments)
Myosin
Actin
______ band
- where myosin and actin overlap (it stays the same width even if the sarcomere is contracted or not)
A band
_____ band
- unbound actin filaments (shorten as Actin is pulled by myosin toward the center of sarcomere)
I band
______ zone
- center of the sarcomere
- Contains roots of myosin thick filaments, and the M line (this cross-links myosin in each myofibril)
H zone
______ lines
- proteins that anchor the entire sarcomere contractile mechanism
Z lines
_______________
- AP travels to axon terminals of motor neurons, then release acetylcholine, which binds to ACh receptors on the sarcolemma then the AP travels into T tubules where depolarization reaches sarcoplasmic reticulum causing voltage gated channels to open and release Ca2+ ions into each myofibril
Motor neuron signal reception
_______________
- Ca2+ binds to troponins monomers along tropomyosin Molecules surrounding the actin fibers (prevents myosin-actin bonding) then Ca2+-Troponin alters the tropomyosin allosterically so now exposes myosin binding sites on actin which myosin heads form cross bridges that move along actin fibers and pulls attached Z disks on end of each sarcomere closer together (muscle contraction)
Sarcomere contraction
_______________
- when the motor nerve signal ends the Ca2+ pumps activate so force Ca2+ back into the sarcoplasmic reticulum
- ATP hydrolyzes to ADP and binds to myosin so weakening the myosin-actin bonds
- without Ca2+ tropomyosin blocks myosin-actin binding
Muscle relaxation
_______________
- Control a particular movement (squatting and rising)
Agonist muscles
_______________
- paired with agonist and control opposite motions
Antagonist muscles
_______________
- move toward the medial plane
Adductors
_______________
- Move away from the medial plane
Abductors
_______________
- Closes a joint
Flexor
_______________
- opens a joint
Extensor
_______________
- white muscle
- Type IIa : oxidative & intermediate
- Type IIb : glycolytic & strong anaerobic bursts
- fatigue quickly & less blood supply, mitochondria, & myoglobin
Fast twitch muscle
_______________
- Red muscle
- Type I : sustained aerobic activity & less force
- Dense, capillaries and more mitochondria & myoglobin
Slow twitch muscle
_________ affect contraction by varying stimulus frequency or intensity
Nerves
Stimulus __________ affects force of individual muscle fiber contraction.
____________ affects number of fibers contracting at once.
Frequency
Intensity
_______________
- all or nothing response
- single nerve impulse causes a single muscle fiber contraction
- may be quick or prolonged (fast or slow) depending on muscle fiber type
Muscle twitch
_______________
- entire muscle contraction depends on many fibers contracting
- strength of contraction depends on the stimulus frequency
- if stimulus repeated before 1st contraction ends then contractions combine (wave summation)
- if repeated result is incomplete tetanus & muscle contracts for prolonged period of time but not at full strength
- frequent stimulus causes muscle at complete tetanus (max force) but rapidly fatigues
Graded response
_______________
- low/moderate movement
- abundant blood O2 to mitochondria recycled ATP by aerobic respiration
- energy source is blood glucose
Aerobic muscle activity
_______________
- intense movement
- if ATP demand exceeds O2 supply then muscle cells have 2 alternative systems (phosphocreatine & glycolysis/lactic acid fermentation)
Anaerobic muscle activity
_______________
- stored in muscle & rapidly supplies ATP anaerobically by Creatine Kinase which transfers phosphate from Creatine to ADP
- reversed when O2 supply rises
Phosphocreatine
_______________
- after a few seconds of O2 limited exertion the muscle fibers use glycolysis to generate ATP until O2 rises
- To maintain this process NAD+ must be recycled by fermentation, yielding Lactic Acid which can be used as an energy source in the liver, kidneys, and heart
- Requires more O2 to oxidize lactic acid (resulting in oxygen debt)
Glycolysis/Lactic Acid Fermentation
_______________
- dense, mineralized, living connective tissue
- Hydroxyapatite crystals Ca5 (PO4)3(OH) and collagen
- innervate & supplied with blood through Haversian and Volkmann’s canals
Bones
2 bones types
__________
__________
Compact
Spongy
_______________
- contact points between bones
- Some are fixed and others articulate
Joints
___________ skeleton
- skull, vertebral column, & rib cage
Axial
___________ skeleton
- limbs, extremities, & pelvis
Appendicular
_______________
- points of connection between bones
Joints
_______________
- immovable dense, connective tissue
Fibrous joint
_______________
- rigid limited movement
- Cartilage as support between bones
Cartilaginous joint
_______________
- movable, synovial fluid filled cavity inside synovial membrane
- Knee, elbow, wrist …
Synovial joint
_______________
- bone cells within solid mineral matrix
- Rigid support
Compact bone
_______________
- structural subunit of compact bone
- Central canal with blood vessels & concentric circles called lamellae
- Osteocytes occupy space is in lamellar matrix
Osteon
_______________ (cancellous)
- porous lightweight
- in epiphyses of long bones & interior of others
Spongy bone
_____________ (arches)
- strong light cavities with marrow
Trabecullae
Osteoclasts are stimulated by _________ to secrete HCl & proteases to digest old bone (osteolysis)
PTH
Osteoblasts are stimulated by __________ to store Ca2+
Calcitonin
_______________
- older trapped osteoblasts that are a part of the living bone matrix and secrete growth hormones
Osteocytes
_______________
- dense, connective tissue, collagen, lack nerves and blood supply, but nourished by perichondrium membrane
Cartilage
_______________
- dense fibrous connective tissue
- connects bones to other bones
Ligament
_______________
- tough fibrous connective tissue at the origin & terminal of muscles
- Cross joints to attach muscle to bone (facilitate or limit movement)
Tendons
_______________
- 4-5 layers of different types of epithelial cells
- avascular (O2 diffuses from dermis)
- Keratinocytes secrete intermediate filaments of tough keratin
- New cells by mitosis in lower layers push older cells up, which bind together and fill with hydrophobic glycolipids & keratin and die (forming outer layers)
- melanocytes (pigment), Langerhans cells (immune), Merkel cells (light touch)
Epidermis
_______________
- thick layer of connective tissue that nourishes epidermis and has a high capillary density
- Supports nerves, glands, smooth muscle, and production of hair & nails
Dermis
_______________
- mostly adipose cells
- fat layer insulates against heat loss
Hypodermis
_______________
- muscles attached to each hair follicle
Arrector pili
Integumentary exocrine glands are __________ & ____________
Sebaceous
Sudoriferous (sweat)
_______________
- skin interacts with circulatory system under sympathetic nerves/endocrine control to constrict or dilate dermis capillaries which shunt excess heat to skin or conserve it under Hypodermis insulating fat layer
Thermoregulation by vasodilation/vasoconstriction
_______________
- dissipates heat by evaporative cooling
Sweating
_______________
- cause hairs to stand up which creates an air boundary layer that prevents heat loss
Arrector pili
Sweat has a (minor or major) role excreting salts, urea, & waste metabolites
Minor
______ radiation helps in the synthesis of vitamin D (via Ca2+ metabolism)
UVB radiation
UV is absorbed by & stimulates further production of _________
Melanin
The skin displays immune protection by preventing infection by pathogens via secreting ________________
Anti-bacterial sebum
_______________
- there is no single sense of touch
- Different types of sensory neuron receptors, detect different types of tactile stimuli
- Free nerve endings, Merkel receptors, Hair receptors, Meisner’s corpuscle’s, Pancinian corpuscles, Ruffini’s corpuscles, & Krause’s bulb
Tactile sensory receptors
_______________
- detect pain in the epidermidis
Free nerve endings
_______________
- Detect light touch or distinguish shapes & textures in the epidermidis
Merkel receptors
_______________
- free nerve endings wrapped around hair follicles that detect pressure or movement against hairs
Hair receptors
_______________
- detect light touch in upper dermis
Meisner’s corpuscles
_______________
- detect deep pressure at the base of the dermis
Pacinian corpuscles
_______________
- sense warmth
_______________
- detect cold
Ruffini’s corpuscles
Krause’s bulbs
3 kinds of causes for small scale mutations
____________
____________
____________
Substitution
Insertion
Deletion
____________
- mutation where 1 base replaces another
- could be a transition (purine for a purine) or transversion (pyrimidine for a pyrimidine)
Substitution
A substitution where a purine base replaces a different purine base is called a ____________
Transition
A substitution where a purine base replaces a pyrimidine base is called a ____________
Transversion
3 kinds of substitution mutations
____________
____________
____________
Silent
Missense
Nonsense
____________
- a substitution mutation that does not alter amino acid sequence
Silent mutation
____________
- a substitution mutation that does alter amino acid sequence
Missense mutation
____________
- A substitution mutation that causes early stop codon
- Results in a non-functional protein
Nonsense mutation
__________ or _________
- can result in a frameshift mutation and completely altering a protein
Insertion or deletion
____________
- jumping genes
- can splice new genetic material into different loci in the genome
- Altering proteins, creating frameshifts, or altering gene regulation
Transposons
____________
- can insert new genetic material into genomes
- Act like a transposons
Viruses
____________
- induce mutations
- UV, ionizing radiation, free radicals, viruses, & transposons
Mutagens
____________
- provides a measure of evolutionary time by comparing accumulated DNA mutations or changes in amino acid sequences of proteins among species
Molecular clock
____________
- Heritable changes over time in populations
Evolution
____________
- due to sexual reproduction, recombination, & mutations
Genetic variation
____________
- Exchange of genes among populations
- Increases variation within populations and decreases reproductive isolation of populations necessary for speciation
Gene flow
____________
- Random divergence in gene pools when populations are isolated
Genetic drift
____________
- in small populations, minor changes in allele frequencies have large affects on later generations (founder effect)
Evolutionary bottleneck
____________
- fittest individuals in a population with traits that aid survival and reproduction contribute more to gene pools of later generations
- May be directional, stabilizing, or disruptive
- Occurs at level of jeans, individuals, kin groups, or populations
Natural selection
____________
- nonrandom mating
- mate choice based on phenotypic characteristics
Sexual selection
____________
- crossing of 2 related species
- Viability : ability of offspring to reproduce
- Leakage : movement of genes among different species (due to hybridization between species or transfer through a viral vector, which causes a horizontal gene transfer in evolution)
Hybridization
____________
- The change in traits that increase in organisms fitness
Occurs at the level of population or species (not individuals)
Adaptation
____________
- The role in organism plays in its ecosystem (habitat, diet, reproductive strategies, migration …)
- Successful adaptations make the organism better suited for this
Niche
____________
- A group of naturally interbreeding organisms that produce new individuals of the same kind
Species
____________
- The development of new species through the evolution of a population of an existing species that is reproductively isolated from the original species
Speciation
A persons temperament is influenced in part by genes
- Certain alleles of dopamine receptor _____ are associated with risk taking behavior and others with emotional stress resistance
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