Active transport - outside the cell is only 5mM. Diffusion...

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Active transport Carrier proteins also provide a mechanism through which the energy changes associated with transporting molecules can be coupled to the use or production of other forms of metabolic energy. Molecules can be transported against a concentration gradient if the transport is coupled to ATP hydrolysis, the absorption of light, the transport of electrons, or the flow of other substances down a gradient - as a source of energy. Typically the K+ concentration inside a mammalian cell is about 100 mM, while that
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Unformatted text preview: outside the cell is only 5mM. Diffusion of potassium out of the cell is favored. Sodium ions and Calcium ions have the opposite concentration gradient. Such gradients are maintained by active transport. ION PUMPS Depends on integral membrane proteins that are capable of selectively binding a particular solute and moving that substance across the membrane- driven by changes in the protein's conformation....
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