Question

what structure in the membrane causes plasma membranes to resist freezing?
channel proteins
cholesterol
nonpolar heads of the phospholipids
unsaturated fatty acid tails
saturated fatty acid tails

Explanation:

• Channel proteins are for transport, not freezing resistance.
• Cholesterol affects membrane fluidity over a range of temperatures but not specifically freezing resistance.
• Phospholipid heads are polar, not non - polar.
• Unsaturated fatty acid tails have double bonds causing kinks, which prevent tight packing and resist freezing.
• Saturated fatty acid tails pack tightly and are more prone to freezing.

Answer:

Unsaturated fatty acid tails