Explain how glucose is used differently as a fuel source in the glycolytic and aerobic energy systems. (4 marks)
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Sample Answer
Glycolytic System:
- Breaks down glucose without oxygen in sarcoplasm
- Produces 2 – 3 ATP molecules through rapid glycolysis
- Results in lactic acid as by-product
- Powers high-intensity exercise 10 – 60 seconds
Aerobic System:
- Complete glucose breakdown with oxygen in mitochondria
- Produces 36 – 38 ATP through Krebs cycle/electron transport chain
- Results in CO2 and H2O as by-products
- Powers prolonged exercise 2+ minutes
Summary
- Glycolytic system sacrifices ATP yield for speed, while aerobic system maximises ATP production through complete glucose oxidation.
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Sample Answer
Glycolytic System:
- Breaks down glucose without oxygen in sarcoplasm
- Produces 2 – 3 ATP molecules through rapid glycolysis
- Results in lactic acid as by-product
- Powers high-intensity exercise 10 – 60 seconds
Aerobic System:
- Complete glucose breakdown with oxygen in mitochondria
- Produces 36 – 38 ATP through Krebs cycle/electron transport chain
- Results in CO2 and H2O as by-products
- Powers prolonged exercise 2+ minutes
Summary
- Glycolytic system sacrifices ATP yield for speed, while aerobic system maximises ATP production through complete glucose oxidation.