Membrane Transport and Facilitated Diffusion

These flashcards cover key concepts related to membrane transport, including types of transport mechanisms and the properties of proteins involved in facilitated diffusion.

Selective Permeability

The ability of the cell membrane to allow certain substances to pass through while restricting others.

Passive Transport

Transport that does not require energy; solutes move with their concentration gradient (high to low).

Active Transport

Transport that requires energy to move solutes against their concentration gradient (low to high).

Diffusion

The spontaneous process resulting in the net movement of molecules from an area of high concentration to an area of low concentration.

Osmosis

The diffusion of water across a selectively permeable membrane, moving from high water concentration to low water concentration.

Facilitated Diffusion

The process in which molecules diffuse across the membrane via transport proteins, increasing the rate of diffusion for certain substances.

Channel Protein

A transport protein that forms a channel in the membrane to allow specific molecules or ions to pass through.

Carrier Protein

A transport protein that undergoes conformational changes to carry substances across the membrane.

Aquaporins

Specific channel proteins that facilitate the transport of water across cell membranes.

Concentration Gradient

The difference in concentration of a substance between two areas, driving the movement of molecules.