What Is The Main Function Of The Phospholipid Bilayer?

The main function of the phospholipid bilayer is to provide structural support for the cell and control what enters and leaves the cell.

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The phospholipid bilayer that this question is asking about is the cell membrane. The cell membrane is made of mostly a double layer of phospholipids, cholesterol, and fatty acids. The layer has a hydrophobic section and a hydrophilic section, and that makes the membrane itself a selectively permeable membrane. This...

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The phospholipid bilayer that this question is asking about is the cell membrane. The cell membrane is made of mostly a double layer of phospholipids, cholesterol, and fatty acids. The layer has a hydrophobic section and a hydrophilic section, and that makes the membrane itself a selectively permeable membrane. This means that some materials can freely diffuse through membrane while others can't go through at all, but the membrane does contain special channels within it to allow for things like facilitated diffusion and active transport, which works against the concentration gradient.

As a biological membrane, the cell membrane has three main functions. One function is to keep materials that could be harmful to the cell outside of the cell. A second function of the cell membrane is to simply give the cell itself its shape. The cell membrane can't do this by itself, so underneath the cell membrane is a cytoskeleton that helps support the cell membrane. The third main function of the cell membrane is to control and allow movement of materials into and out of the cell. Those materials are things like nutrients, ions, waste products, and metabolic products. These types of materials are necessary for the cell to carry on cellular processes within the various organelles contained inside the cell membrane.

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