Plasma Membrane/Transport

Front

What is the plasma membrane?

Back

The plasma membrane is a biological membrane that separates and protects the interior of all cells from the external environment. It is composed of a phospholipid bilayer with embedded proteins.

Front

What is the function of receptor proteins in the plasma membrane?

Back

Receptor proteins are specialized proteins that receive and transmit signals into the cell, allowing the cell to respond to external stimuli.

Front

Define facilitated diffusion.

Back

Facilitated diffusion is the process by which molecules move across a cell membrane through a protein channel, following their concentration gradient without the use of energy.

Front

What role do cholesterol molecules play in the plasma membrane?

Back

Cholesterol molecules help to stabilize the fluidity of the plasma membrane, making it less permeable to very small water-soluble molecules that might otherwise pass freely through.

Front

What are ion channels?

Back

Ion channels are proteins that allow specific ions to pass through the plasma membrane, facilitating the movement of ions in and out of the cell.

Front

What is the difference between active transport and passive transport?

Back

Active transport requires energy to move substances against their concentration gradient, while passive transport does not require energy and moves substances along their concentration gradient.

Front

What are glycoproteins?

Back

Glycoproteins are proteins that have carbohydrate chains attached to them, playing key roles in cell recognition and signaling.

Front

What is the significance of carbohydrates in the plasma membrane?

Back

Carbohydrates on the plasma membrane are important for cell recognition, signaling, and immune response, helping the immune system identify foreign cells.

Front

What is the function of enzymatic proteins in the plasma membrane?

Back

Enzymatic proteins catalyze biochemical reactions at the membrane surface, facilitating various metabolic processes.

Front

Explain the concept of concentration gradient.

Back

A concentration gradient refers to the difference in the concentration of a substance across a space, which drives the movement of molecules from areas of higher concentration to areas of lower concentration.