Question

Compared with a cell with few aquaporin proteins in its membrane, a cell containing many aquaporin proteins will

(A) have a faster rate of osmosis.

(B) have a lower water potential.

(C) have a higher water potential.

(D) accumulate water by active transport.

Short answer

(A) The option “have a faster rate of osmosis” is true.

(B) The option “have a lower water potential” is false.

(C) The option “have a higher water potential” is false.

(D) The option “accumulate water by active transport” is false.

Step-by-step solution

Aquaporin proteins

Aquaporin proteins are membrane proteins that help in the transport of minerals, solutes, and water to different regions through the membrane. These membrane proteins are observed in bacteria, plants as well as animals. These membrane proteins play a significant role in diffusion between cells.

Explanation of option ‘(A)’

Compared to cells with low aquaporins, those with high aquaporins can facilitate osmosis at a high-speed rate. In such cases, the membrane proteins act as ion channels to help in increasing the rate of osmosis. The membrane proteins also facilitate quick diffusion of water from a higher concentration to a lower one.

Thus, in membranes with high aquaporins, osmosis will increase significantly.

Therefore, the given option is true.

Explanation of option ‘(B)’

Aquaporins are membrane proteins that are known to modify the water potential and water gradients in cells. However, a lower number of membrane proteins do not necessarily lower the water potential. This is because water potential depends on the energy necessary to pull water.

Thus, the aquaporin proteins do not decrease the water potential.

Therefore, the given option is false.

Explanation of option ‘(C)’

Aquaporin proteins can help in regulating the water potential and water flow in cells. However, they are not significant enough in increasing the water potential because water potential increases only when the force through which water is being pushed from one region to another increase.

Thus, the aquaporin proteins do not increase the water potential.

Therefore, the given option is false.

Explanation of option ‘(D)’

Aquaporin proteins do not facilitate water movement from one region to another through active transport. Instead, they facilitate the movement of water through diffusion. Thereby, this process creates an osmotic gradient.

Thus, the aquaporin proteins do not accumulate water via active transport.

Therefore, the given option is false.