Ion movements across membranes Flashcards
1
Q
What makes it difficult for ions to cross membranes?
A
- charge
2
Q
What is used to carry ions across membranes?
A
- carrier or channel proteins
3
Q
Give 3 examples of carrier proteins
A
- ATPases, symporters or antiporters
4
Q
What are electrochemical gradients?
A
- movement from high charge to low charge (different inside and outside)
5
Q
How do fish get energy?
A
- ATPases via energy from ATP hydrolysis against electric chemical gradient
6
Q
What is coupled transport?
A
- 2 substances
7
Q
Define symport
A
- both move in same direction (cotransporters)
8
Q
Define antiport
A
- opposite directions (exchangers)
9
Q
What are ionocytes?
A
- ion regulating cells
- mitochondrion-non cells
10
Q
What do ionocytes do
A
- ATP for ion pumps (ATPase, H+ ATPase, Na/K ATPase)
