active transport
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noun
the movement of ions or molecules across a cellular membrane from a lower to a higher concentration, requiring the consumption of energy.
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Origin of active transport
First recorded in 1960–65
Words nearby active transport
active service, active shooter, active site, active splint, active sun, active transport, active vocabulary, active voice, activewear, activin, activism
Dictionary.com Unabridged
Based on the Random House Unabridged Dictionary, © Random House, Inc. 2021
Example sentences from the Web for active transport
British Dictionary definitions for active transport
active transport
noun
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
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition
© William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins
Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
Medical definitions for active transport
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 American Heritage® Stedman's Medical Dictionary
Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.
Scientific definitions for active transport
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.
The American Heritage® Science Dictionary
Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.