Respiration Flashcards
Describe the process of glycolysis
- Glucose phosphorylated to glucose phosphate using 2 phosphates from 2 ATP molecules, making it more reactive
- Splits into 2 molecules of triose phosphate which are oxidised to pyruvate
- 2 NAD reduced to 2 NADH
Where does glycolysis take place?
Cytoplasm
What is the net gain of ATP from glycolysis?
2
Describe the link reaction
- Pyruvate enters matrix of mitochondria by active transport
- Oxidised to acetate, releasing H which reduces NAD
- CO2 produced
- Acetate and coenzyme A produce acetylcoenzyme A
Where does the link reaction take place?
Matrix
Describe the Krebs cycle
- Acetylcoenzyme A reacts with 4C molecule to make a 6C molecule whilst releasing coenzyme A
- 6C molecule oxidised to 5C and then back to 4C
- NAD and FAD reduced
- CO2 produced
Where does the Krebs cycle take place?
Matrix of mitochondria
What is the net gain of ATP from the Krebs cycle and how is it produced?
2, substrate level phosphorylation
Describe oxidative phosphorylation
- NADH and FADH oxidised, donating a H which dissociates into H+ and e-
- Electrons pass down series of electron carriers on inner membrane via redox reactions
- Electrons lose energy which is used to pump H+ across inner membrane, creating H+ gradient
- Some energy lost as heat
- H+ diffuse back through inner membrane via ATP synthase (chemiosmosis)
- Releases energy to form ATP from ADP + Pi
- e- and H+ combine with O2 to form H2O
- Oxygen is terminal electron acceptor
Where does oxidative phosphorylation take place?
Inner membrane of mitochondria
What is the net gain of ATP from oxidative phosphorylation?
34
Which is the only stage included in anaerobic respiration?
Glycolysis
How is NAD regenerated in anaerobic respiration?
NADH is oxidised and the H released reduces pyruvate
What does reduced pyruvate form in anaerobic respiration of animals?
Lactic acid
What does reduced pyruvate form in anaerobic respiration of plants and fungi?
Ethanol and CO2
