Bio200 - Cell Membranes

Flashcards covering key concepts related to cell membranes, including structure, function, transport mechanisms, and relevant cellular processes.

What are the main functions of cell membranes?

Cell membranes separate cells from their surroundings, allow communication, and regulate substance movement in/out of the cell.

What is the fluid mosaic model?

It describes the structure of cell membranes as a mosaic of various components including lipids, proteins, and carbohydrates.

What is responsible for membrane fluidity?

The type of fatty acid tails in phospholipids affects the fluidity of the cell membrane.

How do unsaturated fatty acids affect membrane fluidity?

Unsaturated tails prevent packing, making the membrane more fluid.

Why is cholesterol important for cell membranes?

Cholesterol reduces membrane fluidity at moderate temperatures and hinders solidification at low temperatures.

What is passive transport?

The movement of substances across a cell membrane without the use of energy, including processes like diffusion and osmosis.

What are the types of passive transport?

Simple diffusion, facilitated diffusion, and osmosis.

What is facilitated diffusion?

The process by which substances diffuse through protein channels or carrier proteins in the cell membrane.

What happens during osmosis?

Water diffuses from an area of low solute concentration to an area of high solute concentration.

What is active transport?

The movement of substances against their concentration gradient, requiring energy (ATP).

What is the sodium-potassium pump an example of?

Active transport that maintains the concentration gradients of sodium and potassium ions across the cell membrane.

What is endocytosis?

The process by which a cell takes in substances by forming vesicles.

What are the two types of endocytosis?

Phagocytosis (cell eating) and pinocytosis (cell drinking).

How does the membrane regulate cell-cell recognition?

Through carbohydrates attached to proteins (glycoproteins) and lipids (glycolipids) on the membrane.

What can cause cerebral edema in the context of overhydration?

Water intoxication leading to hyponatremia, which causes swelling of the brain.