14
QuizMultiple Choice
Unit 1 Test
Question 14 • AP Biology - SC5182 A
Cell membranes are a border between the aqueous environment outside the cell and the aqueous environment of the cytoplasm inside the cell. Cell membranes are in part made of phospholipid polymers.
Answer
A
The hydrophilic heads will face outward toward the cell’s exterior and inward toward the cell’s interior. The fatty acids will be tail-to-tail in the center of the membrane.B
The glycerol region in the fatty acid will bend toward the interior of the cell. The choline will bend toward the exterior of the cell.C
The hydrophobic heads will bind with other hydrophobic heads and turn inward to the center of the membrane. The fatty acids will randomly move, giving the membrane fluidity.D
One choline will turn inward toward other choline in the bilayer. The fatty acids will be attracted to the choline and form the interior of the membrane.