The existence of a concentration gradient of glucose across a membrane means that
A) there is a high concentration of glucose on both sides of the membrane.
B) the glucose molecules are more crowded on one side of the membrane than on the other.
C) there is a high concentration of water on both sides of the membrane.
D) the glucose molecules are chemically bonded more tightly on one side of the membrane than on the other.
E) there are more glucose molecules within the bilayer of the membrane than outside of the membrane.

Question

Quizplus · Accepted Answer

A concentration gradient means that there is a difference in concentration between the two sides of a membrane. Therefore, there cannot be a high concentration of glucose on both sides of the membrane (choice A) because that would mean there is no concentration gradient. The molecules being more crowded on one side of the membrane than the other (choice B) is a correct way to describe a concentration gradient. The concentration of water (choice C) is unrelated to the concentration gradient of glucose. The chemical bonding of glucose (choice D) is also unrelated to the concentration gradient. The location of glucose molecules within the membrane (choice E) is not relevant to the concentration gradient.

The Existence of a Concentration Gradient of Glucose Across a Membrane