Cell
The cell membrane (or plasma membrane) surrounds all living cells, and is the cell's most important organelle. It controls how substances can move in and out of the cell and is responsible for many other properties of the cell as well. The membranes that surround the nucleus and other organelles are almost identical to the cell membrane. Membranes are composed of phospholipids, proteins and carbohydrates arranged in a fluid mosaic structure, as shown in this diagram.
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Scientists describe the cell membrane as a fluid mosaic structure because the phospholipids in each layer can move and slide like fluid. It acts like a film of oil on the surface of water. The membrane is like a mosaic because of all the different molecules embedded among the phospholipids. Together, they look like a mosaic. (A mosaic is defined as a surface decoration made by inlaying small pieces of variously colored material to form pictures or patterns.)
The phospholipids form a thin, flexible sheet, while the proteins "float" in the phospholipid sheet like icebergs, and the carbohydrates extend out from the proteins.
Remember that a membrane is not just a lipid bilayer, but comprises the lipid, protein and carbohydrate parts.
Maintaining Homeostasis
Remember that a membrane is not just a lipid bilayer, but comprises the lipid, protein and carbohydrate parts.
Maintaining Homeostasis