Describe the function and structure of cell membrane
Answers
Answer:
Cell membrane is the outer cover of a cell which controls the entry and exit of different materials into the cell. It acts as permable and semipermable layer and allow the useful things such as glucose to enter into it and prevents the entry of harmful things.
Explanation:
The cell membrane (plasma membrane) is a thin semi-permeable membrane that surrounds the cytoplasm of a cell. Its function is to protect the integrity of the interior of the cell by allowing certain substances into the cell while keeping other substances out. It also serves as a base of attachment for the cytoskeleton in some organisms and the cell wall in others. Thus the cell membrane also serves to help support the cell and help maintain its shape.
The cell membrane is a multifaceted membrane that envelopes a cell's cytoplasm. It protects the integrity of the cell along with supporting the cell and helping to maintain the cell's shape.
Proteins and lipids are the major components of the cell membrane. The exact mix or ratio of proteins and lipids can vary depending on the function of a specific cell.
Phospholipids are important components of cell membranes. They spontaneously arrange to form a lipid bilayer that is semi-permeable such that only certain substances can diffuse through the membrane to the cell's interior.
Similar to the cell membrane, some cell organelles are surrounded by membranes. The nucleus and mitochondria are two examples.
Another function of the membrane is to regulate cell growth through the balance of endocytosis and exocytosis. In endocytosis, lipids and proteins are removed from the cell membrane as substances are internalized. In exocytosis, vesicles containing lipids and proteins fuse with the cell membrane increasing cell size. Animal cells, plant cells, prokaryotic cells, and fungal cells have plasma membranes. Internal organelles are also encased by membranes.