The movement of water across a selectively permeable membrane is called.. Osmosis

The movement of water across a selectively permeable membrane is called:

• a- Osmosis
• b- Active transport
• c- Filtration
• d- Diffusion.

You are absolutely correct! The movement of water across a selectively permeable membrane is called (a- Osmosis).

Here's a breakdown of the options and why osmosis is the most fitting answer:

a- Osmosis:

This is the movement of water molecules from a region of low solute concentration (hypotonic solution) to a region of high solute concentration (hypertonic solution) through a selectively permeable membrane that allows water molecules to pass through but not solutes. This process helps maintain balance between the concentrations of solutions on either side of the membrane.

b- Active transport:

This refers to the movement of molecules across a membrane against their concentration gradient, requiring energy from the cell in the form of ATP (adenosine triphosphate). Water movement in osmosis is a passive process and doesn't require energy.

c- Filtration:

This involves the separation of a liquid from a solid or colloid mixture using a filter that allows the liquid to pass through but not the solid particles. While water can be involved in filtration, it's not the same as the specific movement of water molecules across a membrane in osmosis.

d- Diffusion:

This is the movement of molecules from a region of high concentration to a region of low concentration, driven by random thermal motion. While water molecules can diffuse, osmosis specifically refers to the movement of water across a membrane.

Therefore, osmosis is the most accurate term for the movement of water across a selectively permeable membrane as it describes the specific flow of water molecules based on their concentration differences.