Oxidative Phosphorylation

Question 1

Occurs in?

Answer 1

Inner mitochondrial membrane (cristae)

Question 2

Characteristic of cristae and functions

Answer 2

Highly folded to increase SA for

1. Many ETC
2. Many ATP synthase complex

Question 3

2 process of OP

Answer 3

1. Flow of e down ETC from a higher/lower energy level

2. ATP px via chemiosmosis

Question 4

Describe the process of oxidative phosphorylation

Answer 4

1. NADH molecules donate e- to first e carrier in ETC, NADQ reductase
2. free energy is released as high energy e travel downfill
3. the energy is coupled to active pumping of H+ into intermembrane space
4. as mitochondrial membranes is impermeable to ions
   - > p+ grad. is generated for p+ motive force
5. p+ diffuses back via ATP synthase complex into matrix
   - > ADP is phosphorylated to ATP
6. molecular O2 is the final e- acceptor

Question 5

3 importance of molecular O2

Answer 5

1. allows e- carriers to reoxidise
   - > flow of proton through ATP synthase to generate ATP
2. coenzymes(NAD+/FAD) are regenerated
   - pick up more protons
3. reduction of oxygen to form water
   ->removes H+ from matrix
   => generation of p+ gradient across inner mitochondrial matrix