Water enters and leaves plant cells primarily by which process?

• A. Active transport
• B. Facilitated diffusion
• C. Endocytosis
• D. Osmosis

Answer: (D)

Verified step by step guidance

1. Understand the concept of osmosis: Osmosis is the movement of water molecules across a selectively permeable membrane from an area of lower solute concentration to an area of higher solute concentration, aiming to equalize solute concentrations on both sides of the membrane.
2. Identify the key characteristic of plant cells: Plant cells have a rigid cell wall and a selectively permeable plasma membrane, which allows water to move in and out of the cell while regulating the movement of solutes.
3. Recognize that osmosis is a passive process: Unlike active transport, osmosis does not require energy (ATP) because it relies on the natural concentration gradient of water molecules.
4. Eliminate other options: Active transport requires energy to move substances against their concentration gradient, facilitated diffusion involves specific transport proteins for solutes, and endocytosis is a process for engulfing large particles or molecules, none of which apply to water movement in this context.
5. Conclude that osmosis is the correct process: Water enters and leaves plant cells primarily through osmosis, driven by differences in water potential between the inside and outside of the cell.