Ch12 Respiration

Question 1

Glycolysis

Answer 1

1. phosphorylation of glucose to glucose phosphate using 2 ATP
2. splitting of glucose phosphate to 2 triose phosphates
3. NAD is reduced as triose phosphate is oxidised
4. production of 4 ATP and 2 pyruvate

Question 2

ATP production of glycolysis

Answer 2

• 2 ATP used to phosphorylate glucose
• 2 ATP produced per pyruvate molecule formed from triose phosphate (4 ATP)

2 ATP overall

Question 3

Site of glycolysis

Answer 3

cytoplasm

Question 4

Overall energy yield of glycolysis

Answer 4

• 2 molecules ATP
• 2 molecules reduced NAD
• 2 molecules pyruvate

Question 5

Aerobic respiration

Answer 5

requires O2
produces CO2, H2O and ATP

Question 6

Anaerobic respiration

Answer 6

no O2
produces:
-lactate in animals
-ethanol and CO2 in plants
-little ATP

Question 7

4 stages aerobic respiration

Answer 7

1. glycolysis
2. link reaction
3. krebs cycle
4. oxidative phosphorylation

Question 8

Link reaction

Answer 8

1. pyruvate actively transported to matrix in mitochondria
2. pyruvate oxidised to acetate
   - produces CO2 and 2H+
3. NAD is reduced by H+
4. 2C acetate bonds with coenzyme A to produce acetyl coenzyme A

Question 9

Krebs Cycle

Answer 9

1. 2C acetylcoenzyme A + 4C molecule makes 6C molecule
2. 6C molecule -> 2CO2, H+, NADH, FADH, 4C molecule and one ATP (substrate-level phosphorylation)
3. 4C recombines with acetyl CoA

Question 10

Location of link reaction

Answer 10

mitochondria matrix

Question 11

Yield from 1 pyruvate

Answer 11

reduced NAD
reduced FAD
ATP
3 CO2

Question 12

Significance of krebs cycle

Answer 12

1. produce hydrogen carried by NADH to electron transfer chain to provide energy for oxidative phosphorylation
2. regenerates 4C molecule, preventing accumulation
3. source of intermediate compounds used by cell to make other compounds(fatty acids, amino acids ect)
4. breaks down macromolecules into smaller ones

Question 13

Site of oxidative phosphorylation

Answer 13

mitochondria crista

Question 14

Mitochondria adaptations

Answer 14

1. densely packed cristae for large SA for enzymes and proteins involved
2. large number in metabolically active cells

Question 15

ETC and oxidative phosphorylation

Answer 15

1. reduced NAD and FAD are oxidised, releasing proton and electron
2. electron is taken up by electron carrier(reduced)
3. The electron then passes down chain of electron carries through series of oxidation and reduction reactions
4. energy is lost through each reaction
5. energy actively transports protons into inter-membranal space
6. protons diffuse back into cell down concentration gradient through ATP synthase channels
7. electrons combine with proton and oxygen to form water
8. oxygen is final electron acceptor

Question 16

ETC energy

Answer 16

• electrons move down energy gradient
• energy is released in small steps
• less is lost as heat

Question 17

Lipid advantage

Answer 17

-release more than double energy of carbohydrates
- produces 2C molecules
- produces many H atoms used in oxidative phosphorylation

Question 17

Lipid respiration process

Answer 17

1. lipids hydrolysed to glycerol and fatty acids
2. glycerol is phosphorylated
3. produces triose phosphate
4. fatty acid broken into 2C molecule and converted into acetyl CoA
5. enters glycolysis and krebs cycle pathway

Question 18

Protein respiration process

Answer 18

1. hydrolysed to amino acids
2. amine group removed
3. 3C molecules converted to pyruvate
4. 4-5C compounds converted to intermediates in krebs cycle