phys exam 1

physiology

study of how living organisms function - molecular and organ level

organ

have 2 or more of 4 tissue types; usually have all

organ system

group of organs that have an overall function

integrated physiological function

organ systems work together to maintain stability in organism

foundational unit of an organ

small structures in organ that act similarly to carry out organ’s functions; ex - nephrons in kidneys

structural organization/hierarchy of organs

1. cells

2. tissues

3. functional units in organs

4. organs

5. organ system

6. organism

4 tissue types

1. muscle

2. neural

3. epithileal

4. connective

epithelial cell strucrure

• basement membrane: where epithelial cells rest. an extracellular protein layer; anchors tissue

  • side connected to basement membrane = basolateral side

  • opposite side (faces interior aka lumen) = apical side

intracellular fluid

fluid inside all cells; approx 67% of all water in body

extracellular fluid

plasma (7%) and interstitial fluid (26%) together

• plasma - fluid portion that blood is suspended in

• interstitial fluid - fluid between and around cells

steady state vs equilibrium

steady state - components of body are not balanced, but they’re working in tandem

equilibrium - dead body; everything is totally equal

homeostasis

a steady state; variables unchanging as long as there’s energy

dynamic constancy

set point

neg feedback

moves variable opposite of initial change;

ex - if body heats up, will force body to cool back down via sweating, etc

pos feedback

accelerates process; moves variable away from set point

ex - body keeps adding blood clots to wound until entire thing is clotted

feedforward regulation

• anticipates change in variable; tunes homeostatic response

• lessens changes in variable

biological rhythm/circadian rhythm

a feedforward system without detectors; change physiology before the stimulus occurs

ex - circadian rhythm - body increases temperature before waking up in anticipation to increased mobility

hypothalamus

checks time for circadian rhythm (24 hour) without external cues

substance pool

distribution of substances within body; seperate from storage/fat

neg balance

total amount of substance in body decreases

pos balance

total amount of substance in body increases

stable balance

no net change in level of substance

reflex arc

1. stimulus

2. receptors

3. afferent pathway

4. integrating center

5. efferent pathway

6. effector

7. response

carbs

• provide energy/storage

• polar macromolecules; consist of mono/di/poly saccharides

lipids

nonpolar molecules

• saturated - all single bonds

• monounsaturated - 1 c=c

• polyunsaturated - 2(+) c=c

• triglycerides - 3 fatty acids + glycerol

• phospholipids - 2 fatty acids and group w/ phosphate + glycerol

• steroids - cholesterol + derivatives

proteins

amino acids linked w/ peptide bonds

• primary - amino acid sequence

• secondary - beta pleated sheets, alpha helices

• tertiary - 3d shape

• quaternary - polypeptide chains bound together

nucleus

in all cells except skeletal, red blood cells

• stores gene info (DNA) and blueprints for protein synthesis

• nucleolus - where rna synthesis happens

• chromatin - dna

• nuc envelope/pores - lets mRNA into cytoplasm

extracellular matrix

glycocalyx

has glycoproteins - cell recognition

cytoplasm vs cytosol

cytosol - fluid inside cell membrane, outside of organelles

cytoplasm - all fluid inside cell membrane except nucleus

integral protein

embedded in cell membrane; amphipathic

peripheral protein

attached to inside/outside of cell membrane; detects enzyme activity

desmosome

fibers linking adjacent membranes to each other; add elasticity - eg skin, heart; organs that should be elastic

tight junction

tight er membranes; sometimes h2o or ions can still pass

gap junction

protein channels linking cells; allow ions to pass

paracellular pathway

leaves cell halfway thru passing, past tight junction

transcellular pathway

continues all the way thru the cell; no leaving until end

endoplasm reticulum - smooth, rough

smooth - lipid synthesis, ca2+ handling

rough - have ribosomes, package proteins

vesicle

from golgi apparatus; contain modified proteins that fue into cell membrane and move out (if leaving cell)

mitochondria

atp

ribosomes

protein assembly via connecting amino acids

can be free (release proteins into cytosol) or bound (attached to er; release proteins into rough er)

lysosomes

breakdown bacteria, old cells, etc

cytoskeleton

not membrane-bound, maintains shape, movement

golgi aparatus

modifies proteins from rer then puts them into vesicles

peroxisomes

oxidize organic molecules - lipids, toxins, alcohols, etc

genome

chromosome

single dna molecule + associated packaging proteins

gene

sequence of dna for coding of specific protein

triplet

triplet of 3 nucleotides that code for amino acid

proteome

specific proteins made by cell at any time

mRNA

takes info from dna and copies it for single protein

RNA polymerase

binds to protein sequence in gene

promoter sequence

codon

spliceosomes

cut gene data after transcription in premRNA

exons

stay in

introns

get cut out

tRNA

binds covalently to amino acid, anticodon binds to mRNA

anticodon

transcription

copying protein instructions from gene in DNA to mRNA

translation

polypeptides assemble in cytoplasm from mRNA

initiation

tRNA and start codon binds

• longest process; needs initiation factors

• then large ribosome is where tRNA clicks mRNA to amino acid

elongation

new tRNA with linked amino acid links w/ existing polypeptide chain via peptide bond

termination

ribosome hits stop codon; polypeptide chain releases

mutation

change of nucleotide base sequence

transcription factor

what starts transcription…start of process?

proteasome

ubiquitin

tags proteins for degradation

ligand

molecule/ion binding reversible to protein via intermolecular forces

• either opposite charged electrical forces or hydrophobic forces between non polar regions

binding site

ON PROTEIN, where ligand binds to

specificity

specific ligands bind to complementary shape

affinity

how well ligand can bind to protein

• 2 proteins can both have same shape, but one may be pos charged, the other neg….that’s where affinity comes into play

saturation

how many binding sites are filled

based on affinity + ligand concentration

competition

when multiple ligands compete for same binding site

allosteric modulation

modifying ligand can change shape of binding site

covalent modulation

charged chemical groups (usually phosphate) bind to protein

• kinase - enzyme adding phosphate

• phosphatase - enzyme removing phosphatase

modulator ligand

what may bind to protein to change shape

functional site

where ligand binds to protein; “binding site”

cooperativity

proteins can have multiple functional sites influence one another

anabolism

synthesis of organic molecules usually consumes energy

catabolism

breakdown of organi molecules usually releases energy

net flux

which direction reaction heads - either towards products or reactants

chemical equilibrium - net flux = 0

law of mass action

enzyme

protein catalyst; lowers ae not net energy!

active site

enzymes brings reactants (substrates) together via binding close to active sites

cofactor

substrate binding to enzyme changes shape/ability

coenzyme

substance that acts as substrate but acts as “shuttle” to move 1 substrate to other

metabolic pathway

rate limiting enzyme

slowest reaction to occur; think bottleneck

end product inhibition

glycolysis

using glucose as substrate for making atp

results PER GLUCOSE: (remember glucose splits into 2 3-c sugars)

• 2 atp

• 2 nadh

• 2 pyruvate

anaerobic

without o2

aerobic substrate-level phosphorylation

adenosine triphosphate (ATP)

main energy thing for body

ADP pyruvate

from glycolysis, continues into aerobic cycle or krebs

NADH/NAD+

part of etc

lactate

after glycolysis, if there is no o2

acetyl coenzyme a (acetyl coa)

krebs cycle