Question

multiple choice question
which of the following describes passive transport?
○ it requires energy from atp.
○ it does not require an expenditure of energy by the cell itself.
○ it does not require a concentration gradient.
○ it can only be used to move materials up a concentration gradient.

Explanation:

To determine the correct description of passive transport, we analyze each option:

• The first option is incorrect because passive transport does not require energy from ATP (that's active transport).
• The second option is correct. Passive transport (like diffusion, osmosis) relies on natural concentration gradients and does not need the cell to expend energy.
• The third option is incorrect. Passive transport does require a concentration gradient (substances move from high to low concentration).
• The fourth option is incorrect. Moving materials up a concentration gradient (low to high) requires energy, which is active transport, not passive.

Answer:

B. It does not require an expenditure of energy by the cell itself.