Cell membranes and Cells H (unit 3)

Front

What is a hypotonic solution?

Back

A hypotonic solution is one where the concentration of solutes outside the cell is lower than inside the cell, causing water to flow into the cell, potentially leading to cell swelling or bursting.

Front

What is the structure of a cell membrane?

Back

The cell membrane is composed of a phospholipid bilayer with embedded proteins, cholesterol, and carbohydrates, which help regulate what enters and exits the cell.

Front

What is the endosymbiotic theory?

Back

The endosymbiotic theory suggests that eukaryotic cells evolved from prokaryotic cells through a process where larger cells engulfed smaller cells, which then became organelles like mitochondria and chloroplasts.

Front

What is facilitated diffusion?

Back

Facilitated diffusion is a process where molecules move across a cell membrane through protein channels, from an area of high concentration to an area of low concentration, without the use of energy.

Front

What is diffusion?

Back

Diffusion is the movement of molecules from an area of high concentration to an area of low concentration, resulting in the equal distribution of molecules.

Front

What is osmosis?

Back

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

Front

What is active transport?

Back

Active transport is the movement of molecules across a cell membrane against their concentration gradient, requiring energy in the form of ATP.

Front

What role do proteins play in the cell membrane?

Back

Proteins in the cell membrane serve various functions, including transport, acting as channels or carriers, signaling, and providing structural support.

Front

What is the fluid mosaic model?

Back

The fluid mosaic model describes the cell membrane as a dynamic and flexible structure with various proteins floating in or on the fluid lipid bilayer.

Front

What is the function of cholesterol in the cell membrane?

Back

Cholesterol helps to stabilize the cell membrane's fluidity, making it less permeable to very small water-soluble molecules that might otherwise pass freely through.