Plasma membrane Flashcards
(34 cards)
plasma membrane
the phospholipid bilayer and embedded proteins which separate the intracellular and extracellular environment
phospholipid
the main molecule of which membranes are composed. They have a phosphate head and two fatty acid tails
phospholipid bilayer
a double layer of amphiphilic molecules that forms the primary component of cell membranes
hydrophilic
having the tendency to be attracted to and dissolved in water
hydrophobic
having the tendency to repel from and be insoluble in water
amphipathic
molecules with hydrophilic and hydrophobic components
cholesterol
a steroid alcohol that regulates fluidity in the plasma membrane
glycolipid
a phospholipid bound to a carbohydrate
glycoprotein
a protein bound to a carbohydrate
carbohydrate function
cell-cell communication, recognising foreign material, adhesion
integral protein
a protein that is permanently secured to the plasma membrane
transmembrane protein
an integral protein that spans from the intracellular to the extracellular side of the plasma membrane
peripheral protein
a protein that is temporarily secured to the plasma membrane
protein function
transport, enzymes, communication, adhesion
fluid-mosaic model
the ‘fluid component’ comes from the continual lateral movement of the phospholipids, The ‘mosaic’ component comes from the proteins and carbohydrates embedded in the membrane.
passive transport
the movement of molecules through a semipermeable membrane down the concentration gradient without an input of energy
diffusion
the passive net movement of molecules down the concentration gradient (small and/or non-polar molecules)
facilitated diffusion
the passive net movement of molecules down the concentration gradient through a transport protein (large and/or polar molecules)
protein channel
a protein-based pore that selectively enables transport of large and/or polar molecules
protein carrier
a polypeptide that undergoes conformational change to transport molecules
osmosis
the passive net movement of water through a semipermeable membrane down the concentration gradient
hypertonic
high solute concentration
hypotonic
low solute concentration
isotonic
equal solute concentration