Which process describes the movement of water molecules across a semipermeable membrane from an area of higher water concentration to an area of lower water concentration?

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

Answer: (B)

Verified step by step guidance

1. Understand that the problem is asking about the movement of water molecules across a semipermeable membrane, which allows only certain molecules to pass through.
2. Recall that diffusion is the movement of molecules from an area of higher concentration to an area of lower concentration, but it generally refers to solutes, not specifically water.
3. Recognize that facilitated diffusion involves the movement of molecules across a membrane with the help of transport proteins, but it is not specific to water movement.
4. Identify that active transport requires energy to move molecules against their concentration gradient, which is not the case here since water moves from higher to lower concentration naturally.
5. Conclude that the correct process describing water movement across a semipermeable membrane from higher to lower water concentration is osmosis, which is a special type of diffusion specific to water.