symporter
symporter A transport protein that couples the movement of a substance across a cell membrane with the simultaneous movement of ions in the same direction. The substance is ‘pulled’ uphill against its concentration gradient by the flow of the ions down their pre-existing concentration gradient. Hence, it is a form of active transport, powered by the energy stored in the ionic concentration gradient, which is maintained by cellular mechanisms. For example, kidney tubule cells contain a sodium/glucose symporter that exploits the gradient of sodium ions (Na+) across the plasma membrane; for every two Na+ that flow inwards it imports one glucose molecule. Compare antiporter; uniporter.
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Active Transport , Active transport is the movement of molecules up their concentration gradient , using energy.
Concentration Gradients
The concentration of most molec… Transport , Transport is the controlled movement of substances from one part of a cell to another, or from one side of a cell membrane to the other. Because each… Sodium-coupled Transport , sodium-coupled transport The entry of a metabolite into a cell against a concentration gradient, where this entry is coupled to the movement of sodiu… Sodium Pump , sodium pump A mechanism by which sodium ions are transported out of a eukaryotic cell across the plasma membrane. The process requires energy in the… Concentration Gradient , Concentration Gradient
A concentration gradient occurs where the concentration of something changes over a certain distance. For example, a few drops… Cytoplasmic Streaming , cytoplasmic streaming The directional movement of cytoplasm in certain cells, which allows movement of substances through the cell, especially around…
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symporter