Question

Three phospholipids X, Y, and Z are distributed in the plasma membrane as indicated in Figure Q11-14. For which of these phospholipids does a flippase probably exist?

(a) X only
(b) Z only
(c) X and Y
(d) Y and Z

Answer 1

Without seeing Figure Q11-14, the exact phospholipid for which a flippase exists cannot be determined, but flippases are enzymes that maintain the plasma membrane's lipid bilayer by redistributing phospholipids asymmetrically.

Step-by-step explanation:

The question revolves around the presence of flippase, an enzyme that assists in the movement of phospholipids between the layers of a plasma membrane's lipid bilayer.

Phospholipids are major components of the plasma membrane of cells, and they exhibit amphipathic properties, with hydrophilic (water-attracting) heads and hydrophobic (water-repelling) tails. This configuration allows the plasma membrane to be selectively permeable, aiding in the movement of materials through it.

In terms of the question, without seeing Figure Q11-14, it is not possible to give a direct answer about the existence of a flippase for phospholipids X, Y, and Z.

However, we can infer that if any of these phospholipids were not distributed equally between the two layers of the plasma membrane, a flippase might be responsible for their movement and redistribution, ensuring the proper function and fluidity of the membrane.