| A | B |
|---|
| phospholipid | amphipathic molecule with both a hydrophilic end and a hydrophobic end |
| channel, pore, or carrier protein | each allows a specific substance to passively cross the membrane |
| hydrophobic core of the cell membrane | paired fatty acid tails |
| hydrophillic external & internal faces of membrane | charged & polar phosphate heads |
| pump proteins | use ATP to move ligands over the membrane up the concentration gradient |
| glycolipids and glycoproteins | often serve as either cell recognition proteins or components of extracellular matrix |
| receptor proteins | allow cell communication via intracellular signal molecules |
| cholesterol molecules | embedded into the fatty acid tails & reduce membrane fluidity |
| aquaporin | the transport protein specific for water |
| integral membrane proteins | proteins that pass completely through the cell membrane |
| peripheral membrane proteins | proteins that only partially cross the membrane or that are anchored onto the inner or outer face of the membrane |
| cytoskeletal proteins | often interact with membrane proteins to allow cell shape or movement to respond to external conditions |
| plasma membrane | the external cell membrane of a cell |
| cytoplasm | aqueous gel in contact with the inner face of the plasma membrane |
| extracellular fluid | aqueous solution in contact with the outer face of the plasma membrane |
