Compare TWO different energy systems by exploring their duration, sources of fuel and causes of fatigue. Use examples to support your answer. (7 marks)
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Energy Systems Being Compared:
- ATP-PCr System (Phosphocreatine System)
- Aerobic System (Oxidative System)
Similarities
- Both energy systems produce ATP to fuel muscle contractions during exercise activities. They work together seamlessly during most physical activities to meet energy demands.
- Both systems can operate without requiring external oxygen supply from the respiratory system. This allows immediate energy production when exercise begins before breathing rate increases.
Differences – Duration
- The ATP-PCr system operates for very short durations of 10-15 seconds maximum. This occurs because stored ATP and creatine phosphate supplies are limited in muscle cells.
- The aerobic system functions for hours or even days. This happens because oxygen allows continuous fuel breakdown without harmful byproduct accumulation.
Differences – Fuel Sources
- The ATP-PCr system sources fuel from stored ATP and creatine phosphate already present in muscles. This enables immediate energy release without requiring glucose breakdown.
- The aerobic system utilises carbohydrates, fats and proteins as fuel sources. This process requires oxygen to completely break down these substrates.
Differences – Causes of Fatigue
- Fatigue in the ATP-PCr system results from depletion of stored phosphocreatine reserves. For instance, a weightlifter cannot continue once stores are exhausted.
- Aerobic system fatigue occurs due to fuel depletion or oxygen limitations. Marathon runners experience this when glycogen stores become depleted.
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Energy Systems Being Compared:
- ATP-PCr System (Phosphocreatine System)
- Aerobic System (Oxidative System)
Similarities
- Both energy systems produce ATP to fuel muscle contractions during exercise activities. They work together seamlessly during most physical activities to meet energy demands.
- Both systems can operate without requiring external oxygen supply from the respiratory system. This allows immediate energy production when exercise begins before breathing rate increases.
Differences – Duration
- The ATP-PCr system operates for very short durations of 10-15 seconds maximum. This occurs because stored ATP and creatine phosphate supplies are limited in muscle cells.
- The aerobic system functions for hours or even days. This happens because oxygen allows continuous fuel breakdown without harmful byproduct accumulation.
Differences – Fuel Sources
- The ATP-PCr system sources fuel from stored ATP and creatine phosphate already present in muscles. This enables immediate energy release without requiring glucose breakdown.
- The aerobic system utilises carbohydrates, fats and proteins as fuel sources. This process requires oxygen to completely break down these substrates.
Differences – Causes of Fatigue
- Fatigue in the ATP-PCr system results from depletion of stored phosphocreatine reserves. For instance, a weightlifter cannot continue once stores are exhausted.
- Aerobic system fatigue occurs due to fuel depletion or oxygen limitations. Marathon runners experience this when glycogen stores become depleted.
♦♦ Mean mark 55%.