Question

question 9
1.75 pts
which characteristic of a phospholipid contributes to the fluidity of the membrane?
a saturated fatty acid tail
double bonds in the fatty acid tail
cholesterol content
the head
question 10
1.75 pts
red blood cells placed in distilled water will
shrink as sodium moves out of the cells by diffusion
swell as water moves into the cells by osmosis
shrink as proteins move out of the cell by diffusion
remain unchanged because of homeostatic mechanisms
swell as water moves into the cells by active transport

Explanation:

For Question 9, double - bonds in fatty acid tails introduce kinks, preventing tight packing and increasing membrane fluidity. Saturated fatty acid tails pack tightly reducing fluidity, cholesterol regulates fluidity but not the main contributor here, and the head is not related to fluidity in this context.
For Question 10, distilled water is hypotonic to red blood cells. Water moves into cells by osmosis (a passive process), causing them to swell. Sodium moving out would not cause shrinkage in this case, proteins don't typically move out by diffusion in this scenario, and red blood cells don't have homeostatic mechanisms to prevent swelling in distilled water, and water movement is by osmosis not active transport.

Answer:

Question 9: B. Double bonds in the fatty acid tail
Question 10: B. swell as water moves into the cells by osmosis