Plasma Membrane

• The plasma membrane consists of two layers of phospholipids with embedded proteins.
• It separates the inside of the cell from its surroundings, allowing it to maintain homeostasis.
• The plasma membrane is the outermost layer that surrounds all cells.
• Phospholipid molecules have hydrophilic heads that are attracted to water, while their tails are hydrophobic (water-repelling) and repel water.
• Cholesterol is an important component of animal cells but not plant cells.
• Protein molecules can be found on the surface or inside the cell membrane.
• Phospholipid bilayer - The basic structure of the plasma membrane made up of two layers of phospholipids arranged in a specific way.
• The plasma membrane is selectively permeable, controlling what enters or exits the cell.
• Cholesterol molecules are present in the plasma membrane and play a role in maintaining fluidity.
• Cholesterol molecules are also present between the layers of phospholipids.
• Glycolipids and glycoproteins are found on the surface of the plasma membrane and serve as markers for cells.
• Fluid mosaic model - A model describing the organization of proteins within the plasma membrane as a dynamic arrangement with some proteins embedded in the lipid bilayer and others attached to the outside.