Question

When molecules are passively transported across a membrane, the direction of their movement is dictated by the molecule's tendency to move

A) from higher to lower energy.

B) out of a cell.

C) from lower to higher energy.

D) into a cell.

E) in both directions; there is no preference

Answer 1

Passive transport across a membrane moves molecules from an area of higher to lower concentration without the need for energy, often via diffusion or facilitated transport.

Step-by-step explanation:

When molecules are passively transported across a membrane, the direction of their movement is dictated by the molecule's tendency to move from higher to lower concentration. This process, known as diffusion, does not require energy and is driven by a concentration gradient.

Molecules like gases, lipids, and water can passively diffuse through the cell membrane, while others such as glucose, amino acids, and ions may require facilitated transport using specific protein channels.