Cell Membrane | MCQs

Explanation

Facilitated diffusion is a type of passive transport that uses carrier proteins to move specific substances across the cell membrane without energy input.

This process allows cells to regulate the movement of essential molecules, like sugars and amino acids, into or out of the cell.

Explanation

The cell membrane is also known as the plasma membrane.

It is composed of a double layer of lipids, specifically phospholipids.

Explanation

All three processes allow movement in and out of cells:

• Osmosis: Movement of water molecules from high concentration to low concentration through a selectively permeable membrane.
• Diffusion: Random movement of molecules from high concentration to low concentration until equilibrium is reached.
• Active transport: Movement of molecules from low concentration to high concentration using energy (ATP) to pump molecules across the cell membrane.

Explanation

• The correct statement about the fluid mosaic model of membrane structure is: The more unsaturated the fatty acid, the more fluid nature.
• Unsaturated fatty acids have kinks in their tails that prevent the lipids from packing tightly together, thus increasing membrane fluidity.