What is a cell membrane?

Answer

The cell membrane is the outer covering of the cell. It is also called the plasma membrane and is composed of two layers called a lipid bilayer.

The cell membrane protects the cell from destructive forces that attack or enter the cell. A membrane also keeps cells separate from one another. It lets substances into and out of the cell.

Cell membranes consist mainly of phospholipids that have a water-loving or hydrophilic head and water-fearing, hydrophobic tails. When placed in solution, phospholipids spontaneously line up into two layers with their tails facing one another and their heads facing the outside. Water and small molecules move freely in and out of the cell via the membrane.

Embedded in the cell membrane are transmembrane proteins that regulate the passage of larger molecules or ions into and out of the cell. The transmembrane proteins carry molecules and ions from one side of the plasma membrane to the other.

Peripheral proteins lie on the cell's surface and do not penetrate the lipid bilayer. These proteins act as signals to other cells. When an enzyme recognizes a certain protein on a cell's surface, it binds to the protein and starts a reaction. Anchor proteins connect structures within a cell to those outside the cell.

Q&A Related to "What is a cell membrane?"
A cell membrane is found in any cell. The cell membrane is the part of the cell that allows substances in and out of the cell. If I remember correctly, the cell membrane is the thin
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The cell membrane is a selectively permeable lipid bilayer found in all
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The cell membrane or plasma membrane is composed of a lipid bilayer. There are two rows of lipids with their polar heads facing away from each other.
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1. Determine which type of staining method you will need to use. This will dictate how you proceed through the next steps and the specific materials required. 2. Prepare the cell.
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