Which energy source drives active transport like the Na+/K+ ATPase?

Which energy source drives active transport like the Na+/K+ ATPase?

• A. NADH.
• B. Proton gradient.
• C. ATP.
• D. Light energy.

Answer: (C)

Direct energy from ATP hydrolysis powers this pump. The Na+/K+ ATPase is a primary active transporter, meaning it uses the energy released from ATP breakdown to change its conformation and move Na+ out of the cell and K+ in against their concentration gradients. The cycle involves ATP binding and hydrolysis to drive a conformational shift, followed by dephosphorylation to reset the pump. This is different from transport that relies on existing ion gradients (secondary active transport) or processes fueled by light energy. NADH is an electron carrier used to generate ATP or drive other redox reactions, not the direct energy source for this pump, and light-driven pumps exist in some organisms but not in this ATPase.

Direct energy from ATP hydrolysis powers this pump. The Na+/K+ ATPase is a primary active transporter, meaning it uses the energy released from ATP breakdown to change its conformation and move Na+ out of the cell and K+ in against their concentration gradients. The cycle involves ATP binding and hydrolysis to drive a conformational shift, followed by dephosphorylation to reset the pump. This is different from transport that relies on existing ion gradients (secondary active transport) or processes fueled by light energy. NADH is an electron carrier used to generate ATP or drive other redox reactions, not the direct energy source for this pump, and light-driven pumps exist in some organisms but not in this ATPase.