Unit 2 Vocabulary - Membrane Transport

Diffusion

Form of passive transport in which the solute will spontaneously move down the concentration gradient from high to low concentrations

Concentration gradient

Difference in concentration across a membrane

Voltage gated ion channels

Form of passive transport that responds to change in the voltage across the membrane

Ligand gated ion channel

Form of passive transport that responds to the binding of specific ligands to the extracellular or intracellular domain of the channel

Mechanically gated ion channel

Form of passive transport that responds to tension on the membrane and requires a force to be opened

Active transport

Form of transport that requires energy to move solute against the concentration gradient from a low to high concentration

Direct active transport

A process that uses energy to move molecules across a cell membrane against their concentration gradient, such as the sodium potassium pump

Indirect active transport

A process that uses the coordinated movement of one solute up its concentration gradient coupled with another solute movement down to generate the energy needed for active transport

Uniporter

Moves one molecule across the membrane (e.g. glucose transport protein)

Symporter

Moves more than one molecule across the membrane in the same direction

Antiporter

Moves more than one molecule across the membrane in different directions