All terms in this list:
hypertonic: a solution with a hgh solute content
fluid mosaic: the membrane structure: decipting a cellular membrane as a mosaic of diverse protein molecules, embedded in a bilayer of phospholipid molecules
selective permeability: happens when the biological membranes allows some substances to cross more easily than others and blocks the passage of other substances altogether
diffusion: spontaneous movement of a substance down its concentration gradient from where it is more concentrated to where it is less concentrated.
concentration gradient: a region along which the density of a chemical substance increases or decreases. -> when this exists, substances tend to move from where they are more concentrated to where they are less concentrated.
passive transport: the diffusion of a substance across a biological membrane, with NO expenditure of energy.
osmosis: The diffusion of water across a selectively permeable membrane.
tonicity: The ability of a solution surrounding a cell to cause a cell to gain or lose water
isotonic: Referring to a solution that, when surrounding a cell, has no effect on the passage of water into or out of a cell HINT =
hypotonic: Reffering to a solution that, when surrounding a cell, will cause the cell to take up water HINT: less
osmoregulation: an organisms whose body fluids have a solute concentration equal to that of its surroundings. -do not have a net gain or loss of water by osmosis.
facilitated diffusion: The passage of a substance through a specific transport protein across a biological membrane down its concentration gradient
active transport: the movement of a substance across a biological membrance against its concentration gradient, aided by specific transport proteins. REQUIRES ENERGY
endocytosis: Cellular uptakes of molecules or particles via formation of new vesicles from the plasma membrane. =IN(-take)
exocytosis: The movement of materials out the cytoplasm of a cell by the fusion of vesicles with the plasna membrane. EX(it)
phagocytosis: Cellular "eating; a type of endocytosis in which a cell engulfs macromolecules
pinocytosis: Cellular drinking. a type of endocytosis in which the cell takes fluid and dissolved solutes into small membranous vesicles.
receptor-mediated endocytosis: The movement of specific molecules into a cell by the inward budding of a membranous vesicle, which contains proteins with recepto sites specific to the molecules taken in.
aquaporin: a protein channel- transport protein in the plasma membrane of some plant or animal cells that facilitates the diffusion of the water across the membrane