active transport

active transport

n.

The movement of a chemical substance through a gradient of concentration or electrical potential in the direction opposite to normal diffusion, requiring the expenditure of energy: active transport across a cell membrane.

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active transport

The movement of ions or molecules across a cell membrane in the direction opposite that of diffusion, that is, from an area of lower concentration to one of higher concentration. Active transport requires the assistance of a type of protein called a carrier protein, using energy supplied by ATP.

Thesaurus

Noun

1.

active transport - transport of a substance (as a protein or drug) across a cell membrane against the concentration gradient; requires an expenditure of energy drug - a substance that is used as a medicine or narcotic transport - an exchange of molecules (and their kinetic energy and momentum) across the boundary between adjacent layers of a fluid or across cell membranes