Respiration Flashcards
Define Phosphorylation? (1)
⦾ Adding Pi to molecule (1)
Aerobic + Anaerobic respiration similarities? (2)
⦾ Both produce ATP (anaerobic less) (1)
⦾ Both start with glycolysis (1)
What is the structure of mitochondria? (3)
⦾ Matrix (1)
⦾ Inner membrane/Cristae - increase SA to maximise respiration (1)
⦾ Outer membrane (1)
Define coenzyme? (1)
⦾ Molecule which aids enzyme function
⦾ by transferring chemical group to it(1)
Give some examples of coenzymes in respiration? (2)
⦾ NAD + FAD - Transfer H+ (reduce/oxidise) (1)
⦾ CoA - Transfer Acetate between molecules (1)
What are the 4 main stages of Aerobic respiration and where do they occur? (8)
1 ⦿ Glycolysis - Cytoplasm (2)
2 ⦿ Link Reaction - Mitochondria (2)
3 ⦿ Kreb Cycle - Mitochondria (2)
4 ⦿ Oxidative Phosphorylation - Mitochondria (2)
Which respiratory substrates can be used in Aerobic Respiration? (3)
⦾ Glucose (1)
⦾ Fatty acids (1)
⦾ AAs (1)
What are the main differences between Anaerobic and Aerobic respiration? (4)
⦾ NO Link Reaction (1)
⦾ NO Krebs Cycle (1)
⦾ NO Oxidative Phosphorylation (1)
⦾ Glycolysis products converted ethanol or lactate instead. (1)
Where does Glycolysis occur? (1)
What does it make? (1)
What does it split to make the end product?
⦾ cytoplasm (1)
⦾ pyruvate (1)
⦾ glucose (6C) into 2 X Pyruvate (3C) (1)
What are the 2 main stages in glycolysis? (2)
⦾ Phosphorylation (1)
⦾ Oxidation (1)
Explain fully the process of glycolysis?
- Phosphorylation:
⦾ Glucose phosphorylated with Pi (from ATP)
⦾ Forms 1 glucose-phosphate + 1 ADP
⦾ ATP then adds another Pi to glucose-phosphate forming hexose biphosphate
⦾ Hexose biphosphate split into: 2 TP - Oxidation:
⦾ TP oxidised (loses H+)
⦾ Forms 2 Pyruvate
⦾ NAD collects H+ forming 2 X NADH
⦾ 4 ATP produced - but 2 used up in phosphorylation so net gain 2 ATP.
Why does glycolysis occur in the cytoplasm?
Why do the rest of the reactions occur in the mitochondria?
⦾ Glucose can’t cross outer mitochondrial membrane
⦾ Pyruvate can so rest of reactions occur in mitochondria.
What are the 3 main products of glycolysis?
⦾ 2 X NADH
⦾ 2 X Pyruvate
⦾ 2 X ATP
What are the 3 main products of glycolysis used for?
⦾ 2 X NADH - Oxidative Phosphorylation
⦾ 2 X Pyruvate - The Link reaction
⦾ 2 X ATP - Energy
What happens to the pyruvate from glycolysis in Anaerobic respiration? (Yeast)
⦾ Converted to Ethanol or Lactate
Pyruvate → Ethanal (releases CO2) → (NADH to NAD) Ethanol
What happens to the pyruvate from glycolysis in Anaerobic respiration? (Lactate)
⦾ Pyruvate → (NAD to NADH) Lactate
⦿ NAD oxidised
⦾ Catalysed by lactate dehydrogenase
Explain the Link Reaction fully?
1 ⦾ Pyruvate decarboxylated (1 C removed) in form of CO2
2 ⦾ At same time, pyruvate’s oxidised to form acetate + NAD reduced to NADH
3 ⦾ Acetate combines with CoA to form acetyle CoA
How many times does the Link reaction occur per glucose molecule?
⦾ 2 X pyruvate molecules made for every glucose molecule (in glycolysis)
⦾ So Link reaction + Kreb cycle happen TWICE per glucose molecule
What are the 3 main products of the Link reaction?
⦾ 2 X Acetyl CoA
⦾ 2 X CO2
⦾ 2 X NADH
Where do the 3 main products of the Link reaction for use?
⦾ 2 X Acetyl CoA - Kreb cycle
⦾ 2 X CO2 - Released as waste product
⦾ 2 X NADH - Oxidative Phosphorylation
Where does the Kreb cycle occur?
⦾ Mitochondrial matrix
How many times does the Kreb cycle occur?
⦾ Once per pyruvate molecule
Explain the process of the Kreb cycle fully?
1 ⦾ Acetyle CoA (from Link reaction) combines with 4C oxaloacetate to form 6C citrate
2 ⦾ CoA returns to Link reaction to be used again
———————————————————————————–
3 ⦾ Decarboxylation causes CO2 removal
4 ⦾ Dehydrogenisation occurs - H+ used to produce NADH from NAD
———————————————————————————–
5 ⦾ 5C molecule converted to 4C
6 ⦾ Decarboxylation + Dehydrogenisation occur producing 1 X FAD and 2 X NADH
7 ⦾ Substrate-level Phosphorylation occurs where intermediate transfers Pi to ADP
8 ⦾ Citrate now converted to oxaloacetate
What are the products of the Kreb cycle?
⦾ 1 X CoA ⦾ 2 X CO2 ⦾ 1 X ATP ⦾ 3 X NADH ⦾ 1 X FADH2 ⦾ Oxaloacetate
What are the uses of the products of the Kreb cycle?
⦾ 1 X CoA - Reused in Link reaction ⦾ 2 X CO2 - Released as waste product ⦾ 1 X ATP - Energy ⦾ 3 X NADH - Oxidative Phosphorylation ⦾ 1 X FADH2 - Oxidative Phosphorylation ⦾ Oxaloacetate - Regenerated for next use in Krebs
Explain Oxidative Phosphorylation fully?
1 ⦾ H atoms released from NADH + FADH2 when oxidised to NAD + FAD
2 ⦾ H split into H+ and e-
3 ⦾ e- move down ETC, losing energy at each carrier
4 ⦾ Energy being lost is used by carriers to pump protons from mitochondrial matrix into intermembrane spaces
5 ⦾ H+ conc now higher in intermembrane spaces than mitochondrial matrix forming: electrochemical grad. (ion conc. grad.)
6 ⦾ H+ move down electrochemical grad. from intermembrane spaces, across inner mitochondrial spaces into mitochondrial matrix via ATP synthase
7 ⦾ Movement drives ADP + Pi → ATP synthesis
8 ⦾ ATP production driven by H+ ion movement across membrane (e- moving down ETC) - chemiosmotic theory
9 ⦾ In mitochondrial matrix, end of ETC - O (from blood), H+ and e- combine to form water:
1/2 O2 + 2H+ + e- → H2O
10 ⦾ O2 is the final electron acceptor
Explain what Mitochondrial disease affect?
⦾ Affects ATP production
⦾ Affect mitochondria function
⦾ Affect proteins involved in Oxidative Phosphorylation
and Kreb’s cycle function, reducing ATP production.
What may occur as a result of Mitochondrial disease?
⦾ Increased anaerobic respiration to make up for ATP shortage
⦾ So lots of lactate is produced - fatigue + weakness
⦾ Some lactate diffuses into bloodstream - high lactate conc.s in blood
