Illustration of a model for the potassium and sodium ion channels through pores in the plasma membrane of an animal nerve cell: an example of active t

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Illustration of a model for the potassium and sodium ion channels through pores in the plasma membrane of an animal nerve cell: an example of active transport, where solutes (ions, sugars, amino acids) are pumped into cells from a region of lower to higher concentration. This is a reverse of free diffusion, where molecules move from higher to lower concentrations, that is, down the concentration gradient. The sodium/potassium exchange pump is described here: sodium ions (Na+, red spheres) are being actively pumped out of the cell in a compulsory exchange for potassium ions (K+, blue spheres) entering the cell.

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Size: 2515px × 3780px
Photo credit: © FRANCIS LEROY, BIOCOSMOS/SCIENCE PHOTO LIBRARY / Alamy / Afripics
License: Licensed
Model Released: No

Keywords: biological, biology, cell, channel, channels, cytology, ion, mem, membrane, membrne, microbiology, model, plasma, plasmalemma, pore, potassium, sodium, structure