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Active Transport. Molecular Pumps Energy required to transport across a cell membrane Molecules like Ca, Cl , K, and Na ions are pumped across cell membranes to achieve homeostasis Most often energy is supplied by ATP either directly or indirectly Where? –kidneys. Sodium-Potassium Pump.
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Active Transport • Molecular Pumps • Energy required to transport across a cell membrane • Molecules like Ca, Cl, K, and Na ions are pumped across cell membranes to achieve homeostasis • Most often energy is supplied by ATP either directly or indirectly • Where? –kidneys
Sodium-Potassium Pump • Protein transports Na+ and K+ ions up their concentration gradients http://highered.mcgraw-hill.com/sites/0072495855/student_view0/chapter2/animation__how_the_sodium_potassium_pump_works.html
Endocytosis (Into) • Process by which cells ingest external fluid, macromolecules, and other large molecules
Phagocytosis v. pinocytosis • Phagocytosis: movement of large particles or whole cells • Pinocytosis: involves transport of solutes or fluids
Phagocytes • Cells that ingest bacteria and viruses that invade the body. • All lysosomes to fuse with the vesicles that contain what it ingested • Lysosomal enzymes then destroy the bacteria or virus
Exocytosis (out of) • Substance is released from cell through a vesicle that transports the substance to the cell surface and then fuses out of the cell membrane