Cell membrane Flashcards
what is the structure of a cell membrane?
2 layers of phospholipids (phospholipid bilayer)
what is the outside of the cell that supports it and controls what enters and leaves the cell?
the cell membrane
describe the phospholipid bilayer of cell membranes
the head is polar (water loving) the tail is non-polar (water hating)
three types of passive transport
diffusion, facilitated diffusion and osmosis
three types of active transport
protein pumps, endocytosis, exocytosis
which kind of transport spreads from high to low concentration (goes with the concentration gradient) and uses no energy?
passive transport
particles moving from Hugh to low concentration until equilibrium is reached and particles are evenly spaced is called what?
diffusion
diffusion with the help of transport proteins found in the membrane which are selectively permeable is called what?
facilitated diffusion
the diffusion of water through a highly selectively permeable membrane, from high to low concentration is called what?
osmosis
osmosis causes cells to shrink and grow (and burst) as water exits and enters the cell. true or false?
true
which kind of transport goes from low to high concentration (against the concentration gradient) and requires energy?
active transport
transport proteins that require energy to do work
protein pumps
when the cell membrane folds around particle and consumes/ engulfs it to take it into the cell
endocytosis
cell changes shape (cell membrane opens) to force a particle out of the cell
exocytosis
hypertonic solutions
have higher concentrations outside the cell and the water spreads out wards to balance the solution
isotonic solutions
have equal concentrations outside and inside the cell
hypotonic solutions
have higher concentrations inside the cell and the water spreads inwards to balance the solution
