What is the energy source used by the calcium pump during its normal operation?

• A. ATP hydrolysis
• B. NADH oxidation
• C. Proton gradient
• D. Glucose oxidation

Answer: (A)

Verified step by step guidance

1. Understand the function of the calcium pump: The calcium pump is a type of active transport protein that moves calcium ions across a membrane against their concentration gradient, which requires energy.
2. Identify the energy source for active transport: Active transport processes typically use energy derived from ATP hydrolysis, where ATP is broken down into ADP and inorganic phosphate to release energy.
3. Eliminate incorrect options: NADH oxidation, proton gradient, and glucose oxidation are not directly involved in powering the calcium pump during its normal operation. These processes are associated with other cellular functions, such as oxidative phosphorylation or metabolic pathways.
4. Relate ATP hydrolysis to the calcium pump: The energy released from ATP hydrolysis is used to change the conformation of the calcium pump protein, allowing it to transport calcium ions across the membrane.
5. Conclude that ATP hydrolysis is the correct energy source: Based on the mechanism of the calcium pump and the role of ATP in active transport, ATP hydrolysis is the energy source used during its normal operation.