Reference no: EM133261408

1. In an α-helix that traverses the nonpolar part of a membrane bilayer

the nonpolar sidechains (R groups) face the exterior of the helix while the hydrophilic sidechains face the interior of the helix

the hydrophilic sidechains (R groups) face the exterior of the helix while the nonpolar sidechains face the interior of the helix

all the sidechains (R groups) face the exterior of the helix and most or all of the amino acids will have nonpolar sidechains.

all the sidechains (R groups) face the exterior of the helix and most or all of the amino acids will have hydrophilic sidechains.

2. Which of the following statements about cholesterol is NOT true?

Cholesterol wedges between tightly packed nonpolar tails, disrupting van der Waals interactions making the gel phase less solid-like.

The presence of cholesterol in the membranes of animals gives them a wider range of membrane compositions that can achieve acceptable membrane fluidity for proper membrane function.

Membranes that contain cholesterol have membrane fluidity curves with a steeper transition from gel-phase to liquid-disordered phase.

Cholesterol fills in gaps between mobile nonpolar tails, increasing the number of van der Waals interactions making the liquid disordered phase less liquid-like.