BIOLOGICAL MEMBRANES

Osmotic pressure

a colligative property

Colligative property

pressure applied to a pure solvent to prevent osmosis and is related to the concentration of the solution

Osmotic pressure equation

π = iMRT

What does passive transport not require?

ATP

Why does passive transport not require ATP?

because the molecule is moving down its concentration gradient or from an area of higher concentration to an area of lower concentration

What is simple diffusion?

A process where small, nonpolar molecules passively move from an area of high concentration to an area of low concentration until equilibrium is achieved.

Does simple diffusion require a transporter?

No, it does not require a transporter.

Osmosis

describes the diffusion of water across a selectively permeable membrane

Facilitated diffusion

uses transport proteins to move impermeable solutes across the cell membrane

What is active transport?

A process that requires energy to move substances across a cell membrane.

What type of energy does primary active transport require?

ATP

What does secondary active transport rely on?

An existing favorable ion gradient.

What are the two classifications of secondary active transport?

Symport and antiport

What is endocytosis?

A method of engulfing material into cells via the cell membrane.

What is exocytosis?

A method of releasing material to the exterior of cells via the cell membrane.

What is pinocytosis?

ingestion of liquid into the cell from vesicles formed from the cell membrane.

What is phagocytosis?

ingestion of solid material by the cell.