the movement of ions or molecules across a cellular membrane from a lower to a higher concentration, requiring the consumption of energy.
Each inactive tape transport requires two amperes and the one active transport requires 10 amperes.
Preliminary Specifications: Programmed Data Processor Model Three (PDP-3) Digital Equipment Corporation
(biochem, physiol) a process by which molecules are enabled to pass across a membrane from a region in which they are in a low concentration to one of high concentration; this requires the expenditure of energy in metabolism and is assisted by carrier proteins, commonly referred to as pumps
active transport n.
The passage of ions or molecules across a cell membrane against an electrochemical or concentration gradient, or against the normal direction of diffusion.
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.
- Active vocabulary
noun the total number of words a person uses in his own speech and writing Compare passive vocabulary
- Active voice
active voice One of the two “voices” of verbs (see also passive voice). When the verb of a sentence is in the active voice, the subject is doing the acting, as in the sentence “Kevin hit the ball.” Kevin (the subject of the sentence) acts in relation to the ball. Contemporary Examples Hawa also supports […]
(def 1). noun any clothing designed for sporting or recreational activity
engaged in ; characterized by energetic work, participation, etc.; busy: an active life. being in a state of existence, progress, or motion: active hostilities. involving physical effort and : active sports. having the power of quick motion; nimble: active as a gazelle. characterized by , motion, volume, use, participation, etc.: an active market in wheat; […]