LSU BIO 1201 EXAM 2 WITH QUESTIONS AND WELL DETAILED ANSWERS [ACTUAL EXAM 100%]

LSU BIO 1201 EXAM 2 WITH
QUESTIONS AND WELL DETAILED
ANSWERS [ACTUAL EXAM 100%]
why are membranes called phospholipid bilayers? - CORRECT
ANSWER-phospholipids have hydrophilic head and hydrophobic tail,
hydrophobic face inside of cell making 2 layers
what is meant by fluid mosaic? - CORRECT ANSWER-Mosaic of
proteins drifting laterally in fluid bilayer of phospholipids
how are membranes adjusted for different temperatures? - CORRECT
ANSWER-membrane fluidity adjusted by changing the ratio of
unsaturated to saturated fatty acids
how do the relative amounts of saturated and unsaturated fats change? -
CORRECT ANSWER-if you are in a cold environment you want more
saturated fats for your membranes to be fluid; warm environment you
want more saturated fats to make your membranes more solid
what is meant by membrane fluidity? - CORRECT ANSWER-not too
solid, not too fluid
why is fluidity an important property? - CORRECT ANSWERpreserves membrane function
Henrique and Hanson performed experiments with pigs and examined
the effects on the relative amounts of saturated and unsaturated fats.
What did they find? - CORRECT ANSWER-found that membrane
fluidity can acclimate to temperature; pigs raised wearing underwear in a
hot room had subcutaneous fats with higher melting point
what types of molecules can move easily across the membrane? -
CORRECT ANSWER-small nonpolar molecules, gases, steroid
hormones, and water
what is simple diffusion? - CORRECT ANSWER-down the
concentration gradient; doe