BY 108 Chapter Notes - Chapter 6: Symporter, Antiporter, Active Transport
Document Summary
Substances required for growth are sometimes too large to cross the bilayer. Receptor-mediated endocytosis - transfer of specific molecules. Only food particles that fit attach to the receptor. Clathrin - protein that coats the inner pit. Each pit folds inward to form a vesicle low-density lipoprotein - brings cholestrol into the cell to be used in the membranes exocytosis - reverse of endocytosis. Used by plants to send material for cell wall construction through the inread invented by teads membrane. Used by animals to secrete hormones, neurotransmitters, enzymes, etc. Protists use contractile vacuoles for exocytosis active transport - moves substance against the concentration gradient. Uses selective protein channels like facilitated diffusion. Makes cells independent from environmental conditions sodium-potassium pump - moves sodium and potassium ions across the membrane. Process found in all animal cells coupled transport - uses energy from 1 molecule"s gradient to move another molecule.
