Biology Flashcards
mismatch repair system
enzymes scan, locate, excise, and replaced mismatched pairs missed by DNA polymerase
when do fungi reproduce sexually
when life is hard
heterotrophic
must ingest organic molecules
example of convergent evolution
bat and bird wings
by how many bonds do A and T bond
two
nervous tissue
main component of the brain, spinal cord, nerves, regulates and controls body functions and activity
western blot
used on protein segments, probes used are radiolabeled antibodies
telophase
chromatids reach the poles of the cell, elongation continues, nuclear membrane reforms
when does transcription occur in the lac operon
in the presence of lactose
what proteins are made in the cytosol?
proteins for all the other organelles
large subunit
portion of the ribosome that joins amino acids to form polypeptide chains
phospholipids
polar head group and nonpolar tail that are vital in form in the membrane bi-layer
linkage
linked genes do not sort independently, inheriting one gene changes the probability of inheriting the other
parasitic
one participant benefits and the other is harmed
spindle apparatus
array of microtubules that grow outward from centrioles during mitosis
by how many bonds do C and G bond
three
what is the strongest junction
desmosome
sliding clamp
protein that helps keep DNA polymerase tightly associated with the strand
pure-breeding
homozygous
mismatched base pairs
error caused during replication, methylation of guanine causes pairing with T
what proteins are made in the RER?
for the RER, golgi, lysosomes, endosomes, plasma membrane, and secretion
initiation
mRNA, tRNA, and the first amino acid all come together in the ribosome
sex-linked inheritance
patterns of X and Y chromosome inheritance
spirilla
spiral
when is active transport requires
moving things against their gradient or against an action potential
S phase of the cell cycle
DNA replication
chromatin
DNA and protein
restriction endonucleases
enzymes that cut DNA at specific sequences, creating sticky ends
what is the mitotic spindle made of
microtubules
pleiotropy
one single gene contributes to multiple phenotypic traits
point mutation
a single base pair substitution
where are lipids synthesized?
ER
cancer
uncontrolled cell division due to failure of the cell’s normal regulatory mechanisms
DNA
polymer of deoxyribose nucleotides
what is the pH of the mitochondrial matrix
7.8
what system do second messengers operate under
endocrine
what inhibits the lac operon
glucose
phototrophs
capture energy directly from the sun via photosynthesis
dihybrid crosses
used when considering two traits
draw to separate punnett squares and multiply the individual probabilities for each trait
polymorphisms
random variations in genetic sequence among individuals that create variable forms
is phagocytosis specific?
yes
endocytosis
process by which a cell takes up small particles by invagination of the plasma membrane to form a vesicle
frameshift mutation
changes the reading frame
mendels laws
law of segregation
law of independent assortment
law of independent assortment
genes located on different chromosomes assort independently
from 1-23 do the chromosomes increase or decrease in size?
decrease
histone
proteins around which the DNA helix is wrapped when condensed into chromosomes
lysogenic
dormant cycle of the virus when viral DNA is incorporated into host genome but new viruses are not being assembled
rough endoplasmic reticulum
covered with ribosomes that are actively translocating proteins to the ER lumen as they are translated
start of post-translational modifications
transduction
viruses accidentally incorporate host genetic material into their nucleic acids
gene pool
complete set of genes and/or alleles in a population
autocrine system
signaling molecule secreted by a cell bind to receptors on the same cell
bacili
rod shaped
nucleosome
set of 8 histone proteins in a cube shape with DNA coiled around it
vaccine
inactive virus or portion of virus such that the immune system can develop antibodies without infection
incomplete penetrance
various individuals have the same genotype but some have a diseased phenotype and others do not
how do lysosomes form
budding off from the golgi
helicase
unzips the double helix
tumor suppressor genes
protect cells from uncontrolled growth
what are fungi cell walls made of
chitin
pH of the inter-membrane space
6.4
peroxisomes
detoxify chemicals and participate in lipid metabolism
reverse transciptase
virus enzyme that can translate RNA into DNA to be incorporated into the host genome
survival of the fittest
natural selection
individual best suited to its environment will be most likely to survive and pass along its genetic information
prokaryotic flagella
spinning motion, simple helicies of flagellin
metaphase
chromosomes move to the central plate by spindle
could rRNA be considered an enzyme and why
yes because they act in the polymerization of proteins
smooth muscle
walls of blood vessels and lymphatic tracts, non-striated, involuntary
carcinogens
large polycyclic compounds that bind to the DNA and create bulky side groups
nucleoside
base and sugar
post-translational modifications
usually includes the addition of polysaccharides, lipids, phosphates, and occurs at the ER and golgi
genetic imprinting
one gene is expressed differently depending which parent it originated from
how do bacteria reproduce
binary fission
what does A bond with
T
G0 phase of the cell cycle
halt of division
primates
opposable thumbs, nails
proto-onco genes
normal genes that could become oncogenes if mutated
isotonic
same solute concentration inside and outside
are lipids metabolized in the smooth ER?
no
transcription
the first step in gene expression by which DNA is copied to mRNA
surface proteins
peripheral proteins that do not enter the hydrophobic core
what is the bond between amino acids called
peptide bond
do mitochondria use the same genetic code as the nucleus
no
origin of replication
location on the chromosome where replication begins
what make up the cilia and the flagella
microtubules
5’ end
phosphate
cilia
lining on cavities, protrusions on epithelial cells
movement of extracellular material and fluid
what are found in the mitochondrial matrix?
DNA
Granules
ATP Synthase
G1 phase of the cell cycle
growth
anaphase
microtubules shorten drawing chromatids to opposite ends of the cell, unattached microtubules elongate stretching the cell
example of divergent evolution
adaptive radiation
hardy-weinberg equations
p^2+2pq+q^2=1
p+q=1
Hardy-Weinberg assumption (5)
large population
no mutation
no immigration or emigration
random mating
no natural selection
T
thymine
sister chromatids
duplicated chromosome joined at center by a centromere
introns
non-coding DNA spliced out of the mRNA
C
cytosine
what cells are in G0?
fully differentiated neurons and cardiac muscle cells
germ cells
only cells passed on to offspring
phage
virus that infects bacteria
poly-adenosine (poly-A) tail
added to the 3’ end
meiosis
specialized cell division that produces 4 genetically distinct, haploid reproductive cells
golgi apparatus
cellular “post office” for proteins to organize, continue modifications, excrete proteins in vesicles for transport
example of a lytic virus
AIDS
p1 generation
first parental generation, both parents are homozygous for their trait
one TT and one tt
test cross
cross between a homozygous recessive and a dominant phenotype
transport proteins
transmembrane proteins that create tunnels for the passage of ions, proteins, or other substances through the hydrophobic core
mosaicism
different cells in the same individual contain non-identical genotypes
what is the bacterial cell wall made of
peptidoglycan
flagella
longer, use a whip-like motion
haploid
n
how many cycles of replication does a telomere last
50
anatomy
shared parts/organization
transfer RNA (tRNA)
contains an anticodon on one end and is covalently bonded to the associated anticodon
single-stranded binding proteins
coat the individual strands and prevent re-annealing
mitosis
process by which a single cell divides into two identical daughter cells, both diploid
nervous system
communication between cells via electrical potentials on neurons
tight junction
waterproof barrier
lac operon
regulates the expression of lactase in bacteria
degenerative
amino acid sequence will not give the DNA sequence because each amino acid has multiple codons
wild type
normal or typical phenotype
cholesterol
amphipathic molecule with a steroid and polar region, inserted between phospholipids at high concentrations in eukaryotic cells
muscle cell types
cardiac, smooth, skeletal
messenger RNA (mRNA)
complementary RNA copied from DNA template stand
nondisjunction
chromosomes fail to separate properly during anaphase
semi-conservative
each new formed stand of DNA is made up of one old strand paired with one new strand
metastasis
spreading of a cancer from one tissue or organ to another
small subunit
portion of the ribosome that reads mRNA
mychorrhizae
symbiosis between fungi and plant roots
nucleus
where the DNA is stored, surrounded by a dual bi-layer membrane
fossils
records may reveal past shared traits
probability of EITHER/OR
add
integral proteins
proteins with multiple segments embedded within the phospholipid bilayer
example of co-dominance
blood type
what hormones bind to intracellular receptors
lipid soluble
recognition sequence
specific base sequence recognized by an endonculease
exon
coding sequence in mature mRNA, stay in the nucleus
hypertonic
high solute concentration outside, water flows out
telomeres
long sections of repetitive DNA found at the ends of each chromosome
lichen
symbiosis between fungi and algae
commensalism
one participant benefits and the other is neutral
what is the waterproof junction
tight junction
diploid
2n
G
guanine
immature mRNA
contains introns, not processed
divergent evolution
process by which species develop different forms and even new species from a common ancestor
A
adenine
tubulin
globular protein that polymerizes to microtubules
facilitated diffusion
doesnt require ATP
translation
the process by which ribosomes create proteins
epithelial tissue
lines the cavities and surfaces of blood vessels and organs
phylogeny
shared evolutionary history
do males or females more easily contract x-linked traits
Males
5’ cap
altered nucleotide at 5’ end of transcript
external chemicals/radiation
pyrimidines dimerize when exposed to radiation, chemicals may cause alkylation of base functional groups
myosin
motor protein
3’ end
-OH
vector
segment of DNA used to transfer a desired sequence into the cell
gram negative
stain pink
thin cell wall
no endospores
two membranes (on either end of the cell wall)
conjugation
F+ to F-
sex pilus
juxtacrine
signaling requires direct contact between two cells
niche
the specific status or role an organism plays in its ecosystem
where does translation occur
cytoplasm and rough ER
hyphae
long, intertwining branches
p^2
homozygous dominant
centromere
region of the chromosome that joins the two sister chromatids
osmosis
diffusion of water across a semi-permeable membrane
f1 generation
offspring from the p1 generation
all Tt
example of cilia
respiratory/nervous/reproductive systems
mutualistic
both participants benefit equally
species distinction
organisms classified as different species should not be able to mate with one another and produce viable, fertile offspring
incomplete dominance
dominant and recessive phenotypes blended in heterozygotes
can DNA leave the nucleus
no
mature mRNA
ready for translation, had a 5’ cap and a poly-A tail
how many recessive alleles does a tumor suppressor gene require to lose function
two
what function do proto-onco genes fill
cell division, cell cycle, growth, apoptosis
spontaneous hydrolysis
DNA reacts in solution spontaneously
amine groups react with water to a carbonyl
DNA base hydrolyzed to a hydroxyl
semi-discontinuous
the leading strand is synthesized continuously and the lagging strand is synthesized in okazaki fragments
skeletal muscle
voluntary control of somatic nervous system, striated
RNA polymerase
reads the template strand 3’ to 5’ creating a pre-mRNA transcript that matches the coding strand, with U for T
intracrine system
singaling molecules bind to receptors inside the same cell, never secreted
post-transcriptional processing
large sections of introns are spliced out
what is the purpose of a telomere
provide a buffer region of non-coding DNA so that the loss of DNA doesn’t impact a gene
alternative splicing
exons can be assembled in various orders following intron removal
allele
one of various forms of the same gene
what mutations are heritable
mutations in germ cells
is pinocytosis specific?
no
gene
segment of DNA that codes for a protein
mutations
any change in DNA sequence
G2 phase of the cell cycle
growth
neutral mutation
does not negatively impact the fitness of the individual
chemotroph
oxidize organic or inorganic compounds for energy
first amino acid
methionine
secondary active transport
no direct coupling of ATP required
pinocytosis
ingestion of extracellular fluid and small particles
what type of tissue is blood
connective
apoptosis
programmed cell death featuring autolysis of cell contents by lysosomes
cocci
spherical
primase
RNA polymerase first constructs short RNA primers on both strands because DNA polymerase can only add to an existing 3’ OH group
desmosomes
weld cells together, protect against stress
what activates the lac operon
cAMP
what does C bond with
G
polymerase chain reaction (PCR)
known DNA sequence
2primers to anneal with DNA on either end of the target sequence
heated to denature helix
primers and taq polymerase added
cooled to allow for annealing
heated for the synthesis of two new strands
evolutionary bottleneck
sudden decrease in the number of individuals in a population
when is nondisjunction most common
meiosis one
tissue organization ordering
organ systems, organs, tissues, cells
viruses
acellular species that cannot survive, grow, or reproduce on their own
law of segregation
alleles segregate independently of one another when forming gametes
endosymbiotic theory
mitochondria evolved from aerobic prokaryotes that were engulfed by an ancient eukaryote
connective tissue
connects, supports, binds, or separates other tissues/organs
genotype
specific alleles held by an individual
example of paracrine molecules
neurotransmitters in the synaptic gap
ribosomal RNA (rRNA)
polymer of which ribosomes are constructed
adaptive radiation
rapid formation of a variety of species from one ancestral species
where are lipids metabolized?
mitochondria
transformation
bacteria pick up DNA from the environment
nucleotide
phosphate, sugar, and base
prophase
nuclear membrane and nucleolus break down, DNA condenses to chromosomes, mitosis spindle forms and connects to the kinetochore
bidirectional
replication proceeds in both directions simultaneously from the origin
hybridization
single stranded pieces of DNA anneal to complementary strands
chromosomes
efficiently package DNA to be stored between divisions and moved during division
what explains the MCAT deviations from phenotypic ratios
linkage
criteria for natural selection (2)
individual must have a polymorphism that provides and evolutionary advantage
advantage must result in the individual producing more offspring
where besides the nucleus is DNA found
mitochondria
embryology
two organisms may have similarities only present during development
benign
tumors growing slowly, have not invaded other tissues, could later be cancerous
phenotype
expression of the gene in terms of visible or observable characteristics
lytic
viral genes are actively being transcribed and new viruses being assembled
infected cells eventually burst to release large numbers of new viruses
how many pairs of chromosomes does a human have?
23
22 autosomes and 1 sex
classification levels
kingdom phylum class order family genus species
where does the centriole attach and when?
the centrosome of the chromosome at the metaphase plate
probability of BOTH/AND
multiply
silent mutation
does not alter the amino acid sequence
chordata
deuterosomes, notochord, gills
malignant
cancerous tumor, exhibiting uncontrolled growth
epigenetic
any heritable phenotype resulting from a modification of gene expression rather than alteration of the genetic code itself
q^2
homozygous recessive
bacterial growth
exponential
crossing over
exchange of genetic material between homologous chromosomes that results in recombinant chromosomes during sexual reproduction
gram positive
stain purple
thick cell wall
endospores
single membrane
actin
protein monomer that polymerizes to microfilaments
active transport
requires ATP
any two fragments cut by the same endonuclease will be
complimentary
polygenic
many genes contribute toward one phenotypic trait
can RNA exit the nucleus
yes
binary fission
distribution of DNA is random, daughter cell may not get a copy
DNA sequencing
sequencing may reveal otherwise hidden connections, add legitimacy to current models
convergent evolution
two individuals happen to have the same or similar form but arrived at the form from very different paths
elongation
addition of amino acids by the formation of peptide bonds
nucleolus
site of rRNA transcription and ribosome assembly
locus
specific physical location of a gene on a chromosome
hypotonic
low solute concentration inside, water flows in
which bases are pyrimidines
C and T (and U)
animalia
multicellular, motile, heterotrophic
what is the pH of a lysosome
5
Base excision
DNA glycosylase excizes the base, other enzymes excise the rest, DNA polymerase and ligase replace the bases
lysosomes
digest cell parts, fuse with phagocytotic vesicles and participate in cell death
DNA ligase
fills in the last nucleotide of the lagging strand and completes the final phosphodiester bond
autotrophic
capable of fixing CO2 and can use it as a carbon source
which bases are purines
A and G
start codon
AUG
adherens junction
strong mechanical attachment
2pq
heterozygous
when does crossing over occur
prophase one
f2 generation
offspring from f1 generation
3: 1 phenotype dominant:recessive
1: 2:1 genotype TT:Tt:tt
helicase
unwinds the DNA and creates a transcription bubble
cardiac muscle
heart walls, striated, involuntary
fluid mosaic model
dual-layer model of the phospholipid bilayer creating a cytosolic and extracellular face, phospholipids are fluid
where do neurotransmitters bind to receptors
post-synaptic membrane
what carbon on RNA has a hydroxyl group
2’
somatic cells
any cell that is not a reproductive cell
eastern blot
used to verify post-translational modification, probes bind to lipids, carbs, phosphate
paracrine system
signaling molecules secreted by one cell bind to receptors on other cells in the local area
eukaryotic flagella
whipping motion, microtubules of tubulin
smooth ER
lipid synthesis and modification
mammalia
warm blooded, vertebrates, hair, live birth
missense mutation
change the codon such that a different amino acid is incorporated
homologues
related, non-identical chromosomes
evolution
any change in the gene pool across generations
example of cell with flagella
sperm
M phase of the cell cycle
mitosis
are fungi auto or heterotrophic
heterotrophic
genetic drift
change in the allele frequency in a population due to random, non-genetic, non-selective factors
unambiguous
given a codon, must know the amino acid
where is rRNA assembled
nucleolus
when do the centromeres split in meisos
meiosis two
is connective tissue dense?
no
microtubule
one of the three cytoskeleton structures, heterodimer of tubulin, move vesicles and organelles
simple diffusion
doesn’t require ATP
co-dominance
both phenotypes are expressed at the same time in a heterozygote
promoter
site where RNA polymerase binds to DNA
endocrine system
hormone signaling
hormones made and secreted in endocrine glands and travel in the bloodstream, then bind to receptors in the membrane of cytosol
saprophytic
eat dead or decaying matter
nucleotide excision
removal of multiple bases surrounding an error
microfilaments
provide the cell with structure, make up the thin filament of the muscle to track along which mysoin and motor proteins move during muscle contraction
cytoskeleton
network of microtubules, intermediate filaments, and microfilaments that provide the cell with structure and highway of intracellular transport
okazaki fragments
short segments of new DNA synthesized on the lagging strand
oncogenes
cancer causing
permanent (or semi permanent) repression
methylation or covalent modifications that prevent or reduce transcription
nonsense mutation
changes a codon to a premature stop codon
example of lysogenic virus
HIV without AIDS symptoms
kinetochore
specialized group of proteins to which the spindle fibers attach directly during mitosis and meiosis
stop codons
UAG
UAA
UGA
phagocytosis
receptor mediated endocytosis that involves ingestion of bacteria and large particles
g protein cascade
changes form, GDP –> GTP on the alpha subunit, alpha attaches andenyl cyclase, which produces cAMP from ATP, cAMP to protein kinase A, phosphorylation
northern blot
southern blot for RNA
southern blot
used to verify the presence/absence of a specific DNA sequence, indicates the relative size of restriction fragments
taq polymerase
from thermophilic bacteria, work at high temperatures
gap junction
tunnels between adjacent cells allowing exchange
limited expressivity
various individuals have the same genotype and show the disease phenotype but individuals are impacted to varying degrees
centrosome
amorphous area of proteins and nucleating factors containing centrioles
organizes microtubules, plays a role in cell division
chromosomal mutations
duplications
deletions
translocations
inversions
membrane receptors
a protein that specifically binds a signaling molecule and initiates a cellular response
examples of frameshift mutations
insertion or deletion
exocytosis
process by which a vesicle on the inside of the plasma membrane fuses with the membrane, dumping its contents into the extracellular environment
carrying capacity
maximum number of individuals an ecosystem or environment can sustain
telomerase
any enzyme that adds length to the telomeres
lactase
enzyme tat digests lactose
termination
release factors read a stop codon, synthesis stops, polypeptide released
proofreading
DNA polymerase often catches and replaces mismatched pairs
when do fungi reproduce asexually
when life is good
why are phages important
vectors can be inserted into phages or plasmids to copy it
