Cell Membrane-AP Bio

Front

What is osmosis?

Back

Osmosis is the movement of water across a selectively permeable membrane from an area of low solute concentration to an area of high solute concentration.

Front

Define diffusion.

Back

Diffusion is the movement of molecules from an area of high concentration to an area of low concentration until equilibrium is reached.

Front

What role does cholesterol play in the cell membrane?

Back

Cholesterol helps to maintain cell membrane fluidity by preventing the fatty acid chains of the phospholipids from packing too closely together.

Front

What is an amphipathic molecule?

Back

An amphipathic molecule is one that has both a hydrophilic (polar) head and a hydrophobic (non-polar) tail, allowing it to interact with both water and lipids.

Front

What are channel proteins?

Back

Channel proteins are integral membrane proteins that facilitate the transport of ions and molecules across the cell membrane by forming pores.

Front

What is the fluid mosaic model?

Back

The fluid mosaic model describes the structure of the cell membrane as a mosaic of various proteins that float in or on the fluid lipid bilayer, allowing for flexibility and movement.

Front

What is the significance of the selectively permeable membrane?

Back

A selectively permeable membrane allows certain molecules to pass through while restricting others, thus maintaining homeostasis within the cell.

Front

How do passive and active transport differ?

Back

Passive transport does not require energy and moves substances down their concentration gradient, while active transport requires energy to move substances against their concentration gradient.

Front

What is facilitated diffusion?

Back

Facilitated diffusion is the process by which molecules pass through the cell membrane via special proteins, without the use of energy, moving from high to low concentration.

Front

What is the role of glycoproteins in the cell membrane?

Back

Glycoproteins serve as recognition sites for cell signaling and communication, and they play a role in immune response.