It also regulates concentrations of inorganic ions

It also regulates concentrations of inorganic ions - It...

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It also regulates concentrations of inorganic ions, like Na + , K + , Ca 2+ , and Cl - , by shuttling them across the membrane. However, substances do not move across the barrier indiscriminately; membranes are selectively permeable. Permeability of a molecule through a membrane depends on the interaction of that molecule with the hydrophobic core of the membrane. Hydrophobic molecules, like hydrocarbons, CO 2 , and O 2 , can dissolve in the lipid bilayer and cross easily. Ions and polar molecules pass through with difficulty. This includes small molecules, like water, and larger critical molecules, like glucose and other sugars. While it is true that water seems to move easily in and out of the cell, the exact dynamics are still being explored. (For the moment, we shall consider that water can move freely across the lipid bilayer.) Ions, whether atoms or molecules, and their surrounding shell of water also have difficulties penetrating the hydrophobic core. Proteins can assist and regulate the transport of ions and polar molecules.
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It also regulates concentrations of inorganic ions - It...

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