PSL 431 MSU Exam 1 Questions and Answers

PSL 431 MSU Exam 1 Questions and
Answers
how the chemical composition of the plasma membrane separates aqueous fluids -
ANSWER-phospholipid bilayer

ICF is high in... - ANSWER-K+

ECF is high in... - ANSWER-Na+

ICF - ANSWER-2/3 of body fluids
-contains organelles and chemicals

ECF - ANSWER-80% interstitial fluid, 20% plasma
-contains chemicals

unsaturated fats _____ membrane fluidity - ANSWER-increase

cholesterol - ANSWER--inserts between phospholipids
-low [ ]- reduces fluidity
-high [ ], increases fluidity

3 proteins in PM - ANSWER-1)integral
2)transmembrane
3)peripheral

integral protein - ANSWER--can pass thru PM/anchored
-hydrophobic regions

transmembrane proteins - ANSWER--anchored/pass thru

peripheral proteins - ANSWER--hydrophilic- can't pass thru PM
-not anchored

ECF and ICF are _____ based solutions - ANSWER-water

solutes that move across PM via passive diffusion - ANSWER-O2, CO2,
N2(hydrophobic)
H2O, urea, glycerol, ethanol(small, uncharged polar)

solutes that move across the plasma membrane via Facilitated Diffusion - ANSWER-

ficks - increase [ ], ________ diffusion - ANSWER-increase

, ficks- increase SA, _____ diffusion - ANSWER-increase - microvilli increase SA

ficks - increase lipid solubility, ______ diffusion - ANSWER-increase - polar can't
pass

ficks - increase MW, ______ diffusion - ANSWER-decrease- bigger takes longer

ficks - increase distance, _________ diffusion - ANSWER-decrease - takes longer to
cover more distance

osmosis rule - ANSWER-water follows solute

increase in ECF -> ICF causes cell to... - ANSWER-swell

.1 mol of glucose= ___ mOSM - ANSWER-100 mOsm

normal osmolality - ANSWER-300 mOsm

hyperosmotic - ANSWER->300, pulls water out of cell

Hypoatremia - ANSWER-Na+ below 135

Hyperatremia - ANSWER-Na+ above 145

what law to use when PM is permeable to solute - ANSWER-ficks

what law to use when PM is NOT permeable to solute - ANSWER-osmotic pressure

tonicity - ANSWER-effect a solution has on cell volume, due to non permeable solute
content

hypotonic - ANSWER-net flux of water into cell= swells

hypertonic - ANSWER-net flux of water out of cell= shrinks

solutes that move according to active transport - ANSWER-large uncharged polar -
glucose, sucrose
ions- Cl-, K+, Na+, Ca+2, HCO3-

channel proteins - ANSWER--ion transport
-tunnel lined with charged AA's
-hydrophobic exterior
-Fast!
-selective

leak channels - ANSWER-always open

gated channels - ANSWER-open/close due to stimulus

ligand gated channels - ANSWER-open/close due to ligand binding