1. Unit 2: Metabolic Processes Glycolysis and Pyruvate Oxidation
SBI4U – Ms. Richardson

2. Glycolysis Occurs in the cytoplasm of plant and animal cells
Process is anaerobic, oxygen is not required
Purpose is to split 6-carbon glucose into 2 molecules of 3-carbon pyruvate

3. Main Reactants: Glucose ATP
Glycolysis
Main Reactants:
Glucose
ATP

4. Main Products: Pyruvate ATP NADH
Glycolysis
Main Products:
Pyruvate
ATP
NADH

5. Glycolysis: Overview 4 ATP produced, 2 ATP used Net 2 ATP produced
2 NADH produced
2 pyruvate produced

6. Glycolysis: Details
Glucose is converted through a series of reactions to fructose-1,6-bisphosphate
bisphosphate – 2 phosphate groups have been added
Phosphate groups are obtained from ATP, so 2 ATP have been used
Fructose-1,6-bisphosphate is converted to 2 glyceraldehyde-3-phosphate (G3P) molecules
Each G3P molecule accepts an H atom (carrying 1 proton and 2 electrons) and electrons are donated to NAD+
NAD+ is reduced to NADH
Each G3P is converted to pyruvate
The reaction requires 2 ATP and produces 4 ATP (net 2 ATP produced)

7. Glycolysis: Summary

8. Glycolysis: Summary Overall chemical equation for glycolysis:
Glucose + 2ADP + 2Pi + 2NAD+ 
2 pyruvate + 2ATP + 2H2O + 2NADH

9. Glycolysis
Glycolysis only transfers 2.1% of free energy available in 1 mol of glucose to ATP
Some energy is released as heat, most is trapped in pyruvate and NADH molecules

10. Pyruvate Oxidation
Intermediate step between glycolysis and Krebs cycle
The 2 pyruvate molecules transported from cytoplasm to the matrix
Aerobic, requires oxygen

11. 2 acetyl-CoA + 2NADH + 2H+ + 2CO2
Pyruvate Oxidation
3 changes occur:
2CO2 removed (1 from each pyruvate)
Pyruvate oxidized to acetic acid, NAD+ is reduced to NADH
Coenzyme A (CoA) attaches to form acetyl-CoA
2 pyruvate + 2NAD+ + 2CoA 
2 acetyl-CoA + 2NADH + 2H+ + 2CO2