Active transport requires ATP energy in plants

Steps:

• Identify energy-consuming movement as active transport, which moves substances against concentration gradients using ATP.
• Evaluate options: passive processes like diffusion or osmosis do not require energy.
• Check each: A and B involve gas absorption via diffusion; D uses transpiration pull for water; C involves ion uptake against gradient.
• Confirm C as active transport via proton pumps in root cells.

Why C is correct:

• Nitrate uptake by root hair cells is active transport, using ATP to move ions against their electrochemical gradient (H+-ATPase pumps protons, creating gradient for nitrate co-transport).

Why the others are wrong:

• A: CO2 absorption by palisade cells occurs via passive diffusion down concentration gradient.
• B: O2 absorption by mesophyll cells is passive diffusion for respiration.
• D: Water transport up xylem relies on passive transpiration pull and cohesion, no ATP needed.

Final answer: C