Glycolysis:
Glycolysis = sugar splitting – 6 C12 = broken down into 2 X 312 – (2 X Pyruvate) – Occurs in cytosol
(cytoplasmic matrix)
Phosphorylation addition makes a molecule more chemically reactive
2 stages in Glycolysis:
Energy investment phase:
- 1 X ATP used to convert Glucose into Glucose 6-phosphate (Hexokinase enzyme catalysation)
- Glucose Phosphate is converted into Fructose 6-phosphate (Phosphoglucoisomerase enzyme
catalysation)
- 1 X ATP used to convert Fructose 6-phosphate into Fructose 1,6-bisphosphate
(Phosphofructokinase enzyme catalysation)
- Aldolase enzyme converts this into 2 x 3 C12 molecule
Energy payoff phase:
(Very complex process – use textbook diagrams) But in summary:
- In a series of reactions – G3P = converted into Pyruvate
- H+ combines with NAD forming NADH
- ADP + Pi combines to form ATP
- Several enzymes used in this process
During Glycolysis:
- No C12 released as CO2
- Glycolysis occurs regardless of the presence of O2
Citric acid/Krebs cycle:
Pyruvate enters mitochondrion via active transport
Converted into acetyl CoA via 3 catalysed reactions:
- Carboxyl group on Pyruvate = fully oxidised – released as CO2 molecule
- Remaining 2C12 molecule = oxidised, E- transferred to NAD+ forming NADH (stores energy)
Glycolysis = sugar splitting – 6 C12 = broken down into 2 X 312 – (2 X Pyruvate) – Occurs in cytosol
(cytoplasmic matrix)
Phosphorylation addition makes a molecule more chemically reactive
2 stages in Glycolysis:
Energy investment phase:
- 1 X ATP used to convert Glucose into Glucose 6-phosphate (Hexokinase enzyme catalysation)
- Glucose Phosphate is converted into Fructose 6-phosphate (Phosphoglucoisomerase enzyme
catalysation)
- 1 X ATP used to convert Fructose 6-phosphate into Fructose 1,6-bisphosphate
(Phosphofructokinase enzyme catalysation)
- Aldolase enzyme converts this into 2 x 3 C12 molecule
Energy payoff phase:
(Very complex process – use textbook diagrams) But in summary:
- In a series of reactions – G3P = converted into Pyruvate
- H+ combines with NAD forming NADH
- ADP + Pi combines to form ATP
- Several enzymes used in this process
During Glycolysis:
- No C12 released as CO2
- Glycolysis occurs regardless of the presence of O2
Citric acid/Krebs cycle:
Pyruvate enters mitochondrion via active transport
Converted into acetyl CoA via 3 catalysed reactions:
- Carboxyl group on Pyruvate = fully oxidised – released as CO2 molecule
- Remaining 2C12 molecule = oxidised, E- transferred to NAD+ forming NADH (stores energy)
