membrane Flashcards
what does amphipathic means in membrance
made up of hydrophobic and hydrophillic regions
name 3 type of membrane
glycerophospholipids,
sphingolipids,
sterols
difference in glycerophospholipids and sphingolipid
first one had 3 carbon glycerol phospholipids and the other has asphingosine backbone and one of the fatty acid chain contributes to it.
what is a cytoplasmic or plasma membrane
it is a selectively permeable barrier that controls what enters and exits a cell.
structure and components of a cellular membrane?
phospholipid bilayer - hydrophilic heads facing outwards and hydrophobic tails facing inwards.
cholesterol - added for stability and flexibility, precenting it from becoming too rigid or fluid.
proteins-integral (span through out)and peripheral ( attached to the surface) proteins.
glycoproteins and glycolipids - aid in cell recognition and communication.
physical properties of cellular membrane
fluidity- phos[holipds and proteins can move laterally within the layer, allowing flexibility.
selectively permeable - hydrophobic only allows movement of small nonpolar molecules.
asymmetry- composition of lipids and protein differs between and inner and outer layer providing specific function.
self-sealing - reseal after small disruption - maintain cellular integrity
difference between diffusion, facilitated diffusion, co-transport and active transport
diffusion - down a concentration gradient
facilitated - down a concentration gradient and requires a carrier or transport protein.
active transport - against con gradient and requires a transport or carrier protein.
co-transport- two substance transported together, using energy from one substance moving down its concentration gradient and one against.
what is symport
type of co transport where substance move in the same direction eg glucose with na ions
what is antiport?
2 substance move in opposite directions
one moves inside the cell and the other moves outside.
eg Na/K pump Na pumped out and k pumped in.
factors effecting diffusions
temperature
size a=or mass of substance
sa
diffusion distance
number of channels
What is the difference between endocytosis and exocytosis?
Endocytosis is the process of taking materials into the cell by engulfing them with the cell membrane. Exocytosis is the process of releasing materials from the cell by fusing vesicles with the cell membrane and expelling their contents.
Why is understanding membrane structure and function important for drug design and delivery?
Understanding membrane structure and function is crucial for drug design and delivery because drugs must interact with and cross cell membranes to reach their targets. This knowledge helps in designing drugs that can effectively enter cells, target specific membrane proteins, or utilize membrane transport mechanisms.
