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KNES 259 - Anatomy and Physiology > Cell Physiology > Flashcards

Cell Physiology Flashcards

1
Q

Homeostasis

A
  • Dynamic Equilibrium of the body
  • Consistency despite external changes
  • Hypothalamus is the body’s control center
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2
Q

What does homeostasis control

A
  • Nutrients / wastes
  • O 2 / CO2 levels
  • pH
  • Water / electrolytes
  • Temperature
  • Blood volume
  • Blood pressure
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3
Q

Negative Feedback

A
  • Stimulus, response, stimulus lessens
  • Errors include over correction/compensation and competing regulators
  • Oscillation is the range that the body is comfortable before a response is triggered
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4
Q

Positive Feedback Loops

A
  • Response reinforces the stimulus
  • Snowball effect
  • an external factor is required to shut off the cycle
  • ex/ labor
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5
Q

Levels of Organization in the body

A
  • Chemical (Molecules)
  • Cells (basic unit of life)
  • Tissue (4 types)
  • Organ
  • Body system
  • Organism
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6
Q

Parts of a Cell

A
  • cell membrane: controls all interaction w extracellular fluid
  • Cytoplasm: cytosol and organelles
  • Nucleus: chromosomes and genes
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7
Q

Variety of Cells

A
  • Shape greatly differs based on function
  • Have different organelles to support what it does
    ex/ RBC is very small and really only has hemoglobin organelle ar it needs to fit into small vessels and carry lots of oxygen
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8
Q

Nucleus

A
  • Main Function is replication and repair
  • Every cell has one EXCEPT:
    1. RBC have none because they need to be able to fold up smaller and they replicate so fast
    2. Muscle cells have multiple because they are so long and need repair units to be frequent enough for efficiency
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9
Q

Ribosomes

A
  • look like the little polka dots in the cell
  • responsible for making protein
  • the free ribosomes make protein for the cell, while attached ribosomes make protein for export
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10
Q

Endoplasmic Reticulum

A

Smooth:
- stores calcium (lots in bone cells)
- Detoxification (lots in liver cells)
- Steroid productions (lots in ovaries)
Rough:
- has ribosomes attached
- makes organelles
- protein production for export
- eg. pancreas makes digestive enzymes for stomach

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11
Q

Golgi Complex (Apparatus)

A
  • repackages proteins made by RER sp they can be transported outside of the cell
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12
Q

Peroxisomes

A
  • filled with oxidative enzymes for:
    1. metabolism - Beta oxidation, lipid synthesis
    2. Detoxify various waste
    products, which makes hydrogen peroxide as a byproduct from converting water with catalase
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13
Q

Lysosomes

A
  • sac of digestive enzymes
  • used for repair and removal of
  • lots in WBC
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14
Q

Proteasomes

A
  • large protein complexes
  • protein digesting organelles that digest tagged proteins (damaged proteins, incorrectly folded proteins,
    proteins no longer needed)
  • With age, may be unable to
    normally remove proteins
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15
Q

Cytoskeleton

A
  • complex protein network
  • like the bone and muscle of a cell for support
  • Three distinct elements
    1. Microtubules - transport secretory vesicles, Form mitotic spindle during cell division
    2. Microfilaments - contractile systems, muscle, Mechanical stiffeners
    3. Intermediate filaments - Help resist mechanical stress, in hair, skin, nails
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16
Q

Centrosome/Centrioles

A
  • there and ready for cell division
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17
Q

Cilia

A
  • directional and controlled movement of particles
  • eg. trachea
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18
Q

Flagella

A
  • on moving cell
  • random non-purposeful movement
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19
Q

Mitochondria

A
  • energy organelle
  • produces ATP
  • TCA or krebs cycle
  • ECT cycle
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20
Q

Aging and our cells

A
  • cells deteriorate over time which results in loss of function and inability to respond to stress
  • Free radical theory: Damage from byproducts of cellular metabolism
  • Mitochondrial theory: A decrease in production of energy weakens cells
  • Genetic theory: aging is programmed by genes, With each replication of DNA –nucleotides are lost
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21
Q

Plasma Membrane Structure

A
  • physical barrier
  • gateway for exchange
  • communication
  • cell structure
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22
Q

Phospholipids

A
  • Polar coline head (outer layer)
  • non-polar fatty acid tails (inner layer)
  • prevents free flow in and out of membrane
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23
Q

Glycocalyx

A
  • Glycoproteins and glycolipids on surface of cell
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24
Q

Glycoproteins and proteins on the cell surface

A
  • Integral (transmembrane) proteins
  • Peripheral proteins (sit on top)
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25
Q

Types of membrane Proteins

A

Ion Channels
Carriers
Receptor sites
Enzymes
Pores
Structural
Cell adhesion

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26
Q

Membrane Permeability

A
  • selectively permeable
  • Permeable to small, uncharged, nonpolar (lipid soluble) molecules
  • transmembrane proteins move polar particles
  • macromolecules use vessels
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27
Q

Passive Membrane Movement

A
  • no energy required
  • powered by gradients (concentration, electrical, and electrochemical)
  • Simple diffusion
  • Facilitated diffusion
  • Osmosis
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28
Q

Simple diffusion

A
  • from high to low concentrations
  • happens bc of random particle collision
  • examples would be oxygen and carbon dioxide as they diffuse from capillaries to RBCs
  • two way movement, consider net
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29
Q

Rate of diffusion depends on

A
  1. temp - the faster it’s moving the more random collisions
  2. concentration gradient (bigger diff = faster diffusion)
  3. Diffusion distance (less distance = faster)
  4. Mass of diffusion substance (bigger = lower velocity = less random collisions)
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30
Q

Diffusion across a membrane depends on

A
  • permeability (can it go through?)
  • Surface area (lots of openings)
  • gradient
  • temp
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31
Q

Osmosis

A
  • water moving towards solutes
  • evening water concentration in relation to solutes
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32
Q

Tonicity

A
  • the number of non diffusible particles “water magnets”
  • Isotonic - no net difference
  • hypotonic - less non diffusible particles
  • hypertonic - more non diffusible particles
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33
Q

Effects of Tonicity

A
  • crenation: cells shrink in hypertonic solution
  • hemolysis: cells rupture in a hypotonic solution
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34
Q

Channel Mediated Facilitated
Diffusion

A
  • uses a protein as a channel with no other interaction
  • channel must be open
  • still according to concentration gradient
  • EX/ Na+ and K+ when channels are open
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35
Q

Carrier Mediated Facilitated
Diffusion

A
  • requires action by the carrier protein
  • Concentration gradient
  • Ex/ glucose carrier
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36
Q

Active transport

A
  • requires energy as it moves against the gradient
  • must use carriers
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37
Q

Primary Active Transport

A
  • requires the use of ATP
  • Na+, K+ Atp pump for prior to nerve impulses
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38
Q

Co-Transport Mechanism

A
  • referred to as secondary active transport
  • does not require ATP
  • powered by concentration of one solute and the other catches a ride
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39
Q

Counter - Transport

A

Similar to co-transport
but each molecule
moves in opposite
directions

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40
Q

Receptor(ligand)-mediated
Endocytosis

A
  • molecules bind to receptor on cell surface
  • then brought in in a vesicle
  • moves LDLs, fat soluble vitamins, iron, and antibodies
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41
Q

Phagocytosis

A
  • process to engulf large molecule from outside of the cell to bring it
  • for ex the WBC response to virus would be to bring it in via phagocytosis then allow the vesicle to bind with lysosomes for destruction
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42
Q

Pinocytosis

A
  • forms a vesicle via the pinching of the membrane
  • used to bring lots of fluid and solutes into the cell
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43
Q

Epithelial Transport

A
  • Combines both diffusion and active
    transport for movement
  • attempts to move the most for the least amount of energy
  • ADD TO THIS AS YOU UNDERSTAND
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44
Q

Cell Communication

A
  • Important for controlling growth, reproduction, and cellular processes
  • Most use ligands (molecules that bind to cell or macromolecules)
  • 3 types of receptors that bind ligands:
  • Channel-linked receptors
  • Enzymatic receptors
  • G protein-coupled receptors
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45
Q

Channel-linked Receptors

A
  • occurs as a result of neurotransmitter binding
  • allows ion channels to open
  • Help initiate electrical changes in muscle and nerve cells
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46
Q

Enzymatic Receptors

A
  • Protein kinase enzymes
  • Phosphorylate other enzymes within the cell
  • turns other enzymes on or off
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47
Q

G-Protein coupled receptors

A
  • Indirectly activate protein kinase enzymes
  • Water soluble so they cant enter the cell without protein
  • Activates G-protein to trigger protein kinase or for another channel to open
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48
Q

Second Messenger Response

A
  • Shape change of binding protein activates 2nd response inside the cell
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49
Q

cAMP response

A
  • Activates protein kinase
  • Rapid amplification
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50
Q

Calcium as a Messanger

A
  • Activated IP3 causes release of Ca2+ from ER
  • DAG and IP3 activate enzymes
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51
Q

Calmodulin

A
  • Protein 2nd messenger
  • Similar to cAMP response
  • Activates protein kinase
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52
Q

Genes

A
  • units of heredity
  • contain DNA
  • each gene has its specific locus (place) on each chromosome
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53
Q

Human Chromosomes

A
  • somatic cells have 46 chromosomes with two sets of diploid pairs (one set from each parent)
  • Gametes (sperm and egg cells) are haploid cells with only 23 chromosomes, produces from meiosis
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54
Q

Cell Division

A
  • process by which cells reproduce themselves
  • G1 phase: lasts 8-10hrs where the cell is metabolically active and duplicates organelles
  • Interphase (s-phase): lasts 8hrs where DNA is replicated
  • G2 Phase: 4-6hr of cell growth
  • Mitosis: PMAT
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55
Q

Chromosomes

A
  • When preparing for cell division DNA is replicated and chromosomes condense
  • Each duplicated (x xhaped) chromosome has two sister chromatids
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56
Q

Mitosis: Prophase

A
  • chromatin condense into chromosomes
  • nuclear wall degenerates
  • centrosomes start to move apart
  • spindles move from centrosomes to chromatids
  • kinetochore proteins appear
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57
Q

Mitosis: Metaphase

A
  • centromeres of chromosomes line up at the midline (metaphase plate)
  • mitotic spindles form
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58
Q

Mitosis: Anaphase

A
  • centromeres split
    sister chromatids move to opposing ends
  • kinetochore microtubules move chromatids towards opposing ends of the cell
  • Nonkinetichore microtubules overlap and push against each other, to elongate the cell
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59
Q

Mitosis: Telophase

A
  • mitotic spindles dissolve
  • chromosomes become chromatin
  • new nuclear membrane forms
  • Cytokinesis: cytoplasm divides, cleavages furrow pinches cell in 2
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60
Q

Checkpoints

A

direct the stages of mitosis and cell growth

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61
Q

G1 checkpoint

A

checks for:
- sufficient nutrients
- big enough cell size
- DNA undamaged

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62
Q

G2 checkpoint

A

Checks for:
- cyclins and cyclin dependent kinases present (2 regulatory proteins)
- Cyclins and Cdks for Maturation promoting factor (MPF) to trigger mitosis

63
Q

External Factors

A
  • things outside of the cell can also cause the start of mitosis
  • e.g., growth factor
64
Q

Density dependent inhibition

A

when cells are crowded they stop dividing

65
Q

Anchorage dependence

A

cells must be attached to substratum to divide

66
Q

Cancer cells

A

have no density dependent inhibition or anchorage dependence

67
Q

Apoptosis

A
  • programmed cell death
  • to protect us for dysfunctional cells
  • tries to get rid of potentially cancerous cells
68
Q

Necrosis

A
  • cell death triggered by inflammation
  • not a good process
69
Q

Meiosis

A
  • sexual reproduction
  • produces haploid chromosomes
70
Q

Meiosis I

A
  • reduces chromosomes from diploid to haploid
  • crossing over: increases genetic variability (little bits of the chromosome switch)
71
Q

Meiosis II

A

produces 4 haploid daughter cells

72
Q

Gregor Mendel

A
  • discovered basic laws of heredity
  • tracked “either-or” characteristics
  • hypothesis:
    1. there are alternate versions of genes called alleles
    2. an organism inherits an allele from each parent
    3. if the 2 alleles at a locus differ, the dominant allele appears
    4. law of segregation: the 2 alleles for a heritable trait separate during gamete formation
73
Q

Dominant Genetic Disorders

A
  • Disorder is expressed if dominant gene is present
  • Seen in heterozygous individuals
74
Q

pedigree

A
  • family tree that describes the interrelationships of parents and children across generations
  • Inheritance patterns of traits can be traced
75
Q

Codominance

A
  • two dominant alleles that distinctly impact one phenotype
76
Q

Incomplete dominance

A
  • Phenotype of F1 offspring is between the phenotypes of the two parental varieties
  • skin color
77
Q

Pleiotropy

A

Where one gene has multiple phenotypic
effects

78
Q

Polygeny

A
  • traits are determined by two or more genes
79
Q

X-linked genes

A
  • men only have one x chromosome so they are either the dominant or the recessive gene
  • woman have both so they can be heterozygous
80
Q

Gene Expression

A
  • having a gene doesnt mean it is expressed
  • Epigenic effects mean we can turn genes on and off based on environmental need
  • histones and methylation change it
81
Q

Phenotype

A

its physical appearance of a specific character

82
Q

Genotype

A

the genetic makeup (alleles) that determine the physical appearance

83
Q

Alleles

A

inherited character on the genes (get one from each parent)

84
Q

locus

A

location on the gene

85
Q

Dominant allele

A

determines organisms appearance when heterozygous and homozygous

86
Q

Recessive Allele

A

no noticeable effect on organism unless homozygous recessive

87
Q

Homozygous

A
  • Has a pair of identical alleles for that gene
  • Either dominant or recessive
88
Q

Heterozygous

A
  • pair of alleles that are different for that gene.
89
Q

ATP

A
  • cell’s energy shuttle
  • provides energy for cell functions
  • energy is released from ATP when phosphate bone is broken via hydrolysis
90
Q

Carbohydrates

A
  • made of carbon, hydrogen, oxygen
  • monosaccarides -
  • disaccharides -
  • polysaccarides -
91
Q

Proteins

A
  • Made of amino acids
  • when broken down AA can be used as energy but better serve other purposes
92
Q

Fats

A
  • glycerol and fatty acids
  • more calories per unit
93
Q

Cellular Respiration

A
  • breakdown of glucose or other fuels in the presence of oxygen to yield ATP
  • stages
    1. glycolysis
    2. preparatory step
    3. citric acid cycle
    4. electron transport system
94
Q

Co Enzymes

A
  • Nad+ becomes NADH (reduced)
  • FAD becomes FADH2
  • they act as H+ shuttles and therefore move hydrogen ions and electrons to the ETS
95
Q

Glycolysis

A
  • 9 sequential reactions
  • Anaerobic (no oxygen needed)
  • 2 ATP and 1 Glucose in
  • 4 ATP, 2 NADH and 2 Pyruvate out (net 2-2-2)
96
Q

Preparatory Step

A
  • transfer into mitochondria - requires transport protein (controlled by thyroid hormone and thymin)
  • loss of CO2
  • irreversible (makes choice to go all the way or turn pyruvate into lactic acid for storage)
  • pyruvate becomes acetyl coA
97
Q

Citric acid cycle

A
  • occurs in mitochondrial matrix (open gelatinous area)
  • 2 acetyl coA therefore two cycles occur
  • for 1 acetyl coA 3NADH, 1 ATP, and 1 FADH2 out
98
Q

Electron Transport Chain

A
  • forms ATP
  • requires oxygen for this step
  • transfers energy from NADH/FADH2 to ADP to for ATP
  • Each NADH produces 3 ATP while each FADH2 can produce 2 ATP
  • produces 32-34 ATP
99
Q

Flow of energy

A
  • starts as glucose
  • creates coenzymes (NADH and FADH2)
  • goes to ETC
  • creates ATP
100
Q

Glucose

A
  • 1 glucose molecule yields 38 ATP
  • oxygen is required for full aerobic process
  • only used around 40% of the energy stored in glucose as the remainder is lost as heat
101
Q

Lactic Acid formation

A
  • when there is not enough oxygen
  • this is reversible
  • allows you to make ATP anaerobically
  • when O2 becomes available it can convert back into pyruvate
102
Q

Back up energy sources

A
  • glycogen (stored for of glucose): quickly converts to glucose and is responsible for 1% of energy stores
  • Fats: 78% of energy stores and have twice the energy of carbs
  • proteins: 21% of energy reserves, but require energy for processing (worst energy source)
103
Q

Protein as Fuel

A
  • AA convert to keto acids
  • low ATP yield
  • last resort for energy (if you are in starvation or only eat protein)
104
Q

Fat as fuel

A
  • beta oxidation is used to form acetyl CoA - which then enters TCA cycle
  • high energy yield
  • most efficient storage of energy but it is a slow process
105
Q

Available energy sources for muscle cell

A
  • ready ATP
  • creatine phosphate (storage of ATP)
  • blood plasma glucose
  • glycogen in liver and muscle
  • gluconeogenesis (liver)
  • fatty acids (diet/storage)
106
Q

Energy systems in exercise

A
  • Immediate: phosphagen (creatine phosphate and ATP), makes 4 moles ATP/min but fatigues in 5-10sec
  • Short term: glycolysis (glucose to glycogen-lactic acid), makes 2.5 mole ATP/ min, and takes 1-2 mins to fatigue
  • Long term: Aerobic (glucose, AA, fatty acids), makes 1 mole ATP/min and lasts 2+ mins
107
Q

DNA

A
  • Double helix model
  • polymer of nucleotides
  • a nucleotide is composed of a nitrogenous base, a sugar, and a phosphate group
  • has 2 antiparallel sugar phosphate backbones with 3’ and 5’ ends
  • nitrogenous bases are paired in the interior
108
Q

DNA Replication

A
  • Each strand acts as template for building a new strand
  • parent unwinds and two daughter strands are built with base pairing rules
  • called semi-conservative replication
109
Q

DNA Replication - Helicase

A
  • first step
  • helicase unwinds helix
  • binding proteins stabilize template strands
  • topoisomerase runs ahead and stabilizes the “over twist” sections ahead of helicase
110
Q

DNA Replication - Primase

A
  • Primase primes strands with RNA
111
Q

DNA Replication - DNA polymerase III

A
  • elongates strand, adding nucleotides to 3’ end only
  • reads parent strand from 3’ to 5’
  • builds the daughter from 5’ to 3’
112
Q

DNA Replication - DNA polymerase I

A
  • replaces RNA primer with proper DNA base nucleotides
113
Q

DNA Replication - Ligase

A

glues the segments together

114
Q

Leading Strand

A
  • able to synthesize a complementary strand continuously
  • moving towards the replication fork
  • primase only adds RNA primer once
  • DNA polymerase III builds continuously towards fork
  • poly I replaces primer
115
Q

Lagging Strand

A
  • synthesized as a series of segments
  • called okazaki fragments
  • joined together by DNA ligase
  • moves away from replication fork
  • primase adds to shorter primer sequence
  • DNA polymerase III adds nucleotides to 3’ end until it reaches next primer (okazaki fragment)
116
Q

Mistake correction in DNA replication

A
  • enzyme cut out and replace damaged stretches of DNA (can be damaged vi sun)
  • chromosome ends get shorter every replication
  • nucleotide sequences called telomeres postpone the erosion at the ends by being “junk DNA”
117
Q

Stem Cells

A
  • telomerase: catalyzes the lengthening of telomeres in germ cells
118
Q

Protein Functions

A
  • transporters/carriers
  • channels/pores
  • antibodies
  • storage and structure
  • hormones and receptors
  • contractile proteins
  • enzymes
119
Q

Enzymes

A
  • type of protein
  • act as a catalyst to speed up chemical reactions
120
Q

Polypeptides

A
  • made up of amino acids
  • folds and bends are the secondary structure
  • consist of one or more polypeptides (quaternary)
121
Q

Protein Synthesis Overview

A
  • directed by DNA
  • one gene codes for one polypeptide
  • the ribosome is the cellular machinery for translation
122
Q

Transcription

A
  • synthesis of mRNA under the direction of DNA
  • in nucleus
  • catalysed by RNA polymerase
  • pries DNA strand apart
  • hooks together RNA nucleotides (following base pairing rules)
    1. Initiation- promoters signal initiation, transcription factor help RNA polymerase to recognize promoter sequence
    2. Elongation- RNA polymerase moves along DNA, untwists double helix, exposes 10-20 DNA bases at a time
    3. Termination– polymerase transcribes polyadenylation sequence (AAUAA) so that the protein knows to stop
123
Q

Between transcription and translation

A
  • pre-mRNA
  • 5’ end receives a modified nucleotide cap
  • 3’ end gets a poly-A tail
  • these help to protect the mRNA nd export it to the cytosol
124
Q

RNA splicing

A
  • removes introns (non-coding) and keeps exons (expressed)
  • spliceosomes use snRNP (small nuclear ribonucleoproteins to recognize splice sites
125
Q

tRNA

A
  • translation uses them to shuttle AA to building polypeptide
  • Each tRNA is specific for an AA
  • anticodon so it binds to a mRNA
  • RNA strand with around 80 nucleotides
  • Aminoacyl-tRNA synthetase joins each AA to the correct tRNA
126
Q

Ribosomes in protein synthesis

A
  • free in cytosol or bound to ER
  • synthesis of all proteins starts on free ribosomes
  • export proteins signalled to ER by signal recognition particle (srp)
  • facilitate coupling of tRNA anticodons with mRNA codons during protein synthesis
  • made of proteins and ribosomal RNA (rRNA)
  • has three binding sites for tRNA
    1. the A site to add
    2. the P site for peptide
    3. the E site for Exit
127
Q

Translation - Initiation

A
  • brings mRNA, initiator tRNA (with first AA- Met) and two subunits of ribosome together
  • start codon
128
Q

Translation - Elongation

A
  • AA are added one by one to polypeptide
129
Q

Translation - Termination

A
  • ribosome reaches a stop codon in mRNA
130
Q

Poly ribosome

A

many ribosomes can translate one mRNA at once

131
Q

Mutations

A
  • one wrong nucleotide leads to the wrong AA which leads to a dysfunctional protein
  • substitutions, insertions, or deletions can lead to nonsense or mutation
132
Q

Cell Junctions - Tight Junctions

A
  • allows no movement between cells
  • E.g., intestine, blood brain barrier
133
Q

Gap junctions

A
  • allows movement of ions between cells (allows a transmission of charge)
  • E.g., heart
134
Q

Desmosomes

A
  • Structural junction
  • withstands stress (especially in areas that need to stretch)
  • E.g., skin, uterus, heart
135
Q

Tissues

A

cells with similar structure and functions
1. Epithelial
2. connective tissue
3. nerve
4. muscle

136
Q

Epithelial Tissue Overview

A
  • covering sheets all over the body
  • glands (endocrine and exocrine)
  • functions: protection, absorption, secretion, ino transport, diffusion, filtration, formation of slippery surfaces
137
Q

Epithelial Tissue types

A
  • simple (single layer) vs stratified (multiple layers)
  • cuboidal, columnar cell (ex/gut)
  • squamous cells - flattened (Ex/lung)
138
Q

Simple Squamous Epithelium

A
  • areas with minimal stress
  • adapted for diffusion and filtration (less distance to go)
  • Ex/ lung alveoli and bowman’s capsule
139
Q

Stratified squamous epithelium

A
  • protects ares with stress
  • defends against microbes
  • Ex/ outer layer of skin, lining of mouth, vagina
140
Q

Transitional epithelium

A
  • cells that can change shape
  • in areas subject to stretching
  • urinary bladder
141
Q

Glands

A
  • Exocrine: secrete substances into ducts (sweat glands, gut)
  • Endocrine: ductless, secrete hormones (thyroid)
  • Paracrine: secrete over short distances
142
Q

The goblet cell

A
  • produces mucin
  • mucin + water = mucus
  • protects and lubricates many internal body surfaces
143
Q

Connective Tissue overview

A
  • most diverse and abundant tissue
  • types: cartilage, bone, blood, fat
  • functions: binds, supports, strengthens, protects, insulates, and compartmentalizes muscle
  • Protein types: collagen (stiff), elastic (stretchy)
144
Q

Structural Elements of Connective Tissue

A
  • extracellular matrix
  • collagen and elastin fibres
  • viscous gel-like ground substance
  • cushions and protects body structures
  • different composition of matrix leads to functional differences
145
Q

Connective Tissue Proper

A
  • two subclasses
    1. Loose connective tissue: gel-like matrix with all three fibers, underlies epithelial tissue (fat cells, WBC, mast cells, fibroblasts)
    2. Dense connective tissue
    *Irregular - collagen and elastin arranged randomly to withstand unknown directions of tension (skin, gut, fibrous capsules of joints and organs)
    *Regular - parallel collagen fibers (some elastin) to withstand stress in one direction (tendons, ligaments)
146
Q

Bone - connective tissue

A
  • Compact: harder haversian systems, forms shafts and ends with marrow space - mostly yellow
  • spongy: trabeculae form lattice like support, spaces may contain red bone marrow
  • bone is 10% cells and 90% matrix
    *Cells are osteoblasts (make bone), osteoclasts (reabsorb bone), osteocytes (mature cells)
147
Q

Cartilage - connective tissue

A
  • transitional tissue from which bone develops
  • maintains shape of certain body parts (nose, ears)
  • cushions vertebrae
  • lines joint cavities
  • fibrocartilage: IV disks, mensici
  • hyaline: embryonic structure (that forms bones later), covers and protects ends of longs
  • elastic cartilage: flexible, outer ear, tip of nose
148
Q

Adipose tissue - connective tissue

A
  • fat cells
  • insulates, protects, stores energy
149
Q

Muscle Tissue

A
  • contractile for force and movement
  • types:
    1. cardiac
    2. smooth
    3. skeletal
150
Q

Nervous Tissue

A
  • signal transmission between brain and nerves
  • cells: neurons and neuroglial cells
151
Q

Repair in Nervous tissue

A
  • regeneration: of damaged site with the same type of tissue
  • fibrosis: proliferation of scar tissue
  • organization: clot os replaced by granulation tissue
152
Q

Capacity for regeneration

A
  • Good/excellent: Et, bone CT, areolar CT, dense irregular CT and blood forming CT
  • moderate: smooth muscle
  • weak: skeletal muscle, cartilage, dense regular CT
  • none or minimal: cardial MT, nervous tissue
153
Q

The Tissues Throughout Life

A

With increasing age:
- Epithelia thin
- Collagen decreases
- Bones, muscles, and nervous tissue begin to atrophy
- Poor nutrition and poor circulation lead to poor health of tissues
- Decreased healing

KNES 259 - Anatomy and Physiology (4 decks)

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