Question

The sodium-potassium pump is an active transport pump that uses energy to pump potassium into cells and sodium out of cells. Why is ATP energy required?

A. to change the shape of the ions
B. to transfer glucose in the same direction as Na+ ions
C. to pump the Na⁺ and K⁺ ions along their diffusion gradient
D. to pump the Na⁺ and K⁺ ions against their diffusion gradient for the membrane
E. to change shape

Answer 1

D. to pump the Na⁺ and K⁺ ions against their diffusion gradient for the membrane

ATP energy is required by the sodium-potassium pump to move Na⁺ and K⁺ ions against their diffusion gradient, a process requiring energy to transport the ions from a region of lower to a region of higher concentration.

Step-by-step explanation:

The reason ATP energy is required for the sodium-potassium pump is D. to pump the Na⁺ and K⁺ ions against their diffusion gradient across the membrane. This action occurs against the ions' natural movement, from a region of lower concentration to one of higher concentration, which requires energy input

ATP provides this energy by transferring its phosphate group to the pump, causing a change in shape of the carrier protein and enabling the transport of ions.

Active transport mechanisms, like the sodium-potassium pump, are essential for maintaining concentration gradients that are crucial for various cellular processes, including nerve impulse transmission. Each cycle of the pump moves three sodium ions out of the cell and two potassium ions into the cell, which helps maintain the appropriate concentration inside and outside of the cell, as well as the electrical gradient important for nerve cells.