The proton pump in plant cells __________.

• A. pumps H⁺ into the cell
• B. generates energy by producing ATP
• C. provides energy for active transport
• D. moves H⁺ and nitrate into the cell
• E. pumps H⁺ out of the cell

Answer: (E)

Verified step by step guidance

1. Understand the role of a proton pump: Proton pumps are integral membrane proteins that move protons (H+) across a biological membrane, creating a proton gradient.
2. Recognize the direction of proton movement: In plant cells, the proton pump actively transports protons (H+) out of the cell, which is against their concentration gradient.
3. Identify the energy source: The proton pump uses energy derived from ATP to move protons out of the cell, which is a form of active transport.
4. Consider the consequences of proton movement: By pumping protons out, the proton pump creates an electrochemical gradient, which can be used to drive other processes, such as nutrient uptake.
5. Connect to broader cellular functions: The proton gradient established by the pump is crucial for processes like nutrient transport and pH regulation within the cell.