membrane transport Flashcards
1
Q
what are the major functions of cell membranes?
A
permeability regulation (leak prevention)
anchoring proteins
energy conservation (via proton gradient)
2
Q
what are the three classes of membrane transporting systems?
A
simple transport
group translocation
ABC systems
see pt lectures
3
Q
what is simple transport?
A
movement mediated by concentration gradients (usually ions)
4
Q
what is group translocation?
A
chemical modification, phosphate is attached to molecule to enter membrane
phosphate comes from energy store in the cell
5
Q
what is the ABC system?
A
translocation across a membrane involving a series of proteins