In osmosis, which direction does water move across a semipermeable membrane?

• A. From a region of higher solute concentration to a region of lower solute concentration
• B. Equally in both directions regardless of solute concentration
• C. From a region of lower solute concentration to a region of higher solute concentration
• D. Only if the membrane is impermeable to water

Answer: (C)

Verified step by step guidance

1. Understand the concept of osmosis: it is the movement of water across a semipermeable membrane from a region of lower solute concentration to a region of higher solute concentration.
2. Recognize that the semipermeable membrane allows water molecules to pass but restricts solute particles, creating a concentration gradient.
3. Recall that water moves to balance solute concentrations on both sides, so it flows toward the side with more solute to dilute it.
4. Note that water does not move from higher to lower solute concentration, nor does it move equally in both directions unless concentrations are equal.
5. Confirm that the membrane must be permeable to water for osmosis to occur; if it is impermeable to water, no osmosis happens.