Lec4 Flashcards
The movement of molecules and ions from one location to another
transport.
are transmembrane proteins that function as selective pores, through which molecules or ions can diffuse across the membrane.
Channels
channels can be either passive or active , and limited mainly to ions or water.
T/F?
F, always passive
do not have pores that extend completely across the membrane.
carrier proteins
The membrane proteins that carry out primary active transport
pumps.
the two substances are moving in the same direction through the membrane
symport secondary transport
transport in which the downhill movement of protons drives the active (uphill) transport of a solute in the opposite direction.
Antiport secondary transport
The movement of substances against or up a gradient of chemical potential.
active transport.
different permeabilities, K+ and Cl– initially 1will diffuse across the membrane at same rates.
T/F?
F, different rates.
In biological systems, membranes are usually more permeable to K+ than to Cl-
T/F?
T
Transport through channels is always passive, and limited mainly to ions or water.
T/F?
T
Passive transport on a carrier also called?
facilitated diffusion
