Cell Transportation Flashcards
simple diffusion
the passive movement of particles from areas of high concentration to low concentration through a selectively permeable membrane
what molecules are usually diffused in simple diffusion?
oxygen, carbon dioxide, urea, and ethanol
facilitated diffusion
the passive transport of small/non-polar molecules through the integral protein
what is required for facilitated diffusion?
a concentration gradient and a channel protein
active transport
the use of energy from the hydrolysis of ATP to move ions or large molecules across the cell membrane
active transport requires
ATP and movement against a concentration gradient
sodium - potassium pump
follows a repeating cycle of pumping 3 sodium ions out of the axon (of neurons) and 2 potassium ions pumped in
osmosis
the net movement of water from low solute concentration to high solute concentration through a partially permeable membrane
isotonic
an area/solution that is equal in solute concentration
hypotonic
an area/solution that has a low solute concentration
hypertonic
an area/solution that has a high solute concentration
solute
a substance dissolved in another substance
cholesterol
makes phospholipids in the bilayer pack more tightly and regulates fluidity and flexibility of the membrane
