The presence of cholesterol in the plasma membranes of some animals
A) enables the membrane to stay fluid more easily when cell temperature drops.
B) enables the animal to remove hydrogen atoms from saturated phospholipids.
C) enables the animal to add hydrogen atoms to unsaturated phospholipids.
D) makes the membrane less flexible, allowing it to sustain greater pressure from within the cell.
E) makes the animal more susceptible to circulatory disorders.

Question

The presence of cholesterol in the plasma membranes of some animals 
A) enables the membrane to stay fluid more easily when cell temperature drops. 
B) enables the animal to remove hydrogen atoms from saturated phospholipids. 
C) enables the animal to add hydrogen atoms to unsaturated phospholipids. 
D) makes the membrane less flexible, allowing it to sustain greater pressure from within the cell. 
E) makes the animal more susceptible to circulatory disorders.

alphadxg · Answer

Cholesterol is a temperature buffer for the plasma membrane.  It helps maintain fluidity at lower temperatures and it helps maintain integrity at higher temperatures. So the answer would be A.