Question

The majority of water molecules moving across plasma membranes by osmosis do so via a process that is most similar to _______ 

• facilitated diffusion
• cotransport 
• simple diffusion
• active transport
• a process that requires energy from the cell

Answer 1

Answer Facilitated Diffusion

Facilitated diffusion is a passive transport process during which molecules move down their concentration gradients through transport proteins. Facilitated diffusion uses transport protein but do not require ATP. For the transport of water Aquaporins are there.

Cotransport is a type of active transport in which more than one molecules can be transported simultaneously, either in same direction (symport) or opposite (antiport)

In simple diffusion only concentration gradient is required and the diffusion takes place.

In active transport ATP is required and carrier proteins are also required.

A process that requires energy from the cell is known as Active process.