Respiration Flashcards
1
Q
Aerobic respiration
A
- breakdown of organic compounds like carbohydrate, in a series of enzyme catalysed reactions using oxygen to produce ATP. ATP breakdown releases energy
2
Q
Anaerobic respiration
A
- breakdown of organic compounds like carbohydrate, in a series of enzyme catalysed reactions without oxygen to produced ATP
3
Q
First step of glycolysis
A
- activation of glucose by phosphorylation to form glucose phosphate. This requires 2 ATP to be used
4
Q
Second step of glycolysis
A
- splitting of glucose phosphate into 2 molecules of triose phosphate (an extra phosphate group is added to each molecule)
5
Q
Third step of glycolysis
A
- oxidation of triose phosphate, NAD reduced
6
Q
Forth step of glycolysis
A
- each glycerate 3 phosphate (G3P) gives away 2 phosphates forming pyruvate. 4 ATP formed (net gain of ATP)
7
Q
What is the net gain of glycolysis?
A
- 2 ATP, 2 pyruvate, 2 NADH
8
Q
Substrate level phosphorylation
A
- when a phosphate group is transferred from a substrate molecule to ADP in order to produce ATP
- does not use ATP synthase
9
Q
Link reaction/oxidative decarboxylation
A
- pyruvate oxidised to acetate, producing reduced NAD and releasing carbon dioxide
- acetate combines with coenzyme A to produce acetyl coenzyme A
10
Q
Net gain of link reaction/ oxidative decarboxylation
A
- 1 NADH, 1 CO2, 1 acetyl-coenzyme A (doubled)
11
Q
Krebs cycle/ citric acid cycle
A
- acetylcoenzyme A reacts with a four-carbon molecule, releasing coenzyme A and producing a six-carbon molecule that enters the Krebs cycle
- in a series of oxidation-reduction reactions, the Krebs cycle generates reduced coenzymes and ATP by substrate-level phosphorylation, and carbon dioxide is lost
12
Q
Products of krebs/citric acid cycle per cycle
A
- 3 NADH, 1 reduced FAD, 1 ATP, 2 CO2 (doubled if per glucose molecule)
13
Q
First step of oxidative phosphorylation
A
- If oxygen present, NADH and FADH2 move from cytoplasm into the matrix, where there are oxidised releasing protons and high energy electrons.
Electrons are passed to electron transport chain (ETC).
14
Q
Second step of oxidative phosphorylation
A
- Passage of electrons from one carrier to the next releases energy - this is used to actively pump H+ ions into the intermembrane space from the matrix (against their electrochemical gradient); the energy gradient that exists allows for its gradual release, so less is loss as heat.
15
Q
Third step of oxidative phosphorylation
A
- The electrons, along with protons, are used to reduce oxygen to water. Oxygen is therefore final electron acceptor of the ‘ETC’ of oxidative phosphorylation.