Question

which of the following describes a form of passive transport?
a membrane proteins act as an enzyme to break down atp and use the energy to move particles against the concentration gradient.
b large molecules are brought into the cell by wrapping the cell membrane around the molecules to form a vesicle.
c membrane proteins use the energy of the cells resting potential to move particles against the concentration gradient.
d membrane proteins provide a pathway for larger particles to move across the cell membrane and bring the cell and environment closer to equilibrium.

Explanation:

• Option A: This describes active transport as it uses ATP energy to move particles against the concentration gradient.
• Option B: This is endocytosis (a form of active transport for large molecules).
• Option C: Using energy (even from resting potential) to move against the gradient is active transport.
• Option D: Membrane - protein - facilitated movement towards equilibrium (down the concentration gradient) without using ATP is a form of passive transport (facilitated diffusion).

Answer:

D. Membrane proteins provide a pathway for larger particles to move across the cell membrane and bring the cell and environment closer to equilibrium.