Plasma Membrane Flashcards
functions (5)
compartmentalisation
medium for reactions (link reaction)
controls what passes in and out of cells
cell signalling and self recognition
vesicles
glycoproteins
cell signalling
drugs and hormones and antibodies bind to them
carrier proteins
active transport and facilitated diffusion
transport molecules and ions across the membranes
factors affecting membrane permeability
solvents (dissolve lipids so structure is lost)
temp
glycolipids and glycoproteins (4)
act as receptors for cell signalling
antigens
sites for drugs, hormones and antibodies to bind to
form hydrogen bonds with surrounding water molecules
diffusion
the net movements of particles from an area of high concentration to an area of low concentration this continues until the particles are evenly distrubuted
small, non polar molecules
factors affecting diffusion
concentration gradient
thickness of exchange surface
surface area
temp
facilitated diffusion
carrier and channel proteins
some larger molecules, ions and polar molecules
doesnt require energy
carrier proteins in facilitated diffusion
move large molecules into and out of cells down a concentration gradient
the molecule attached to the protein, changes its shape and is released on the other side
channel proteins
form pores in the membrane for charged particles to diffuse through down a concentration gradient
active transport
this uses energy to move molecules and ions across membranes against a concentration gradient
carrier proteins
carrier proteins in active transport
ATP is used to move the molecules against a concentration gradient
they attach to the carrier protein changing its shape causing it to be released on the other side
osmosis
the diffusion of water molecules across a partially permeable membrane and down a water potential gradient
