Hormones facilitated diffusion regulated

Membrane proteins carry out a wide range of critical functions in cells, and they include passive and active transporters, ion chamiels, many classes of receptors, cellular toxins, proteins involved in membrane trafficking, and the enzymes that facilitate electron transport and oxidative phosphorylation. For example, the voltage-gated ion channels that facilitate the passive diffusion of sodium and potassium across the axonal membrane are responsible for the formation of an action potential. Active transport proteins establish ion gradients and are necessary for the uptake of nutrients into cells. Soluble hormones bind to membrane receptors, which then regulate the internal biochemistry of the cell. 

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