ATP-PC
What does ATP stand for?
Adenosine triphosphate.
Does anaerobic glycolysis require oxygen?
No, it does not require oxygen.
Does aerobic glycolysis require oxygen?
Yes, it requires oxygen.
What is the stored form of carbohydrate in the body?
Glycogen.
What fuel source does the ATP-PC system primarily use?
Phosphocreatine (PC/creatine phosphate).
What is the main fuel source for anaerobic glycolysis?
Muscle glycogen (stored carbohydrate).
What are the two main waste products produced during aerobic glycolysis?
Carbon dioxide, heat and water
What is the stored form of fat in the body?
Triglycerides.
During what approximate duration of maximal intensity exercise is the ATP-PC system the predominant energy system?
Approximately 10 seconds of maximal intensity exercise.
What by-product is associated with anaerobic glycolysis?
Hydrogen ions (H+) and lactate are associated with this system.
Name two fuel sources that can be used by the aerobic system.
Carbohydrates (glycogen/glucose) and fats (triglycerides/fatty acids).
Where is glycogen stored in the body?
Liver and skeletal muscle.
Explain why the ATP-PC system is useful for explosive movements such as a 100 m sprint start.
It produces ATP very quickly, has the highest rate of ATP production and does not require oxygen, making it suitable for explosive movements.
Explain why anaerobic glycolysis becomes more dominant after the ATP-PC system decreases its contribution.
ATP-PC stores become depleted quickly, so anaerobic glycolysis provides a faster way to resynthesise ATP using glycogen without oxygen.
Explain why the aerobic system is suited to endurance activities such as marathon running.
It produces large amounts of ATP, can use fats as a fuel source and can continue for long durations when oxygen is available.
Explain why carbohydrates are preferred over fats during high-intensity exercise.
Carbohydrates provide ATP more rapidly than fats and are therefore preferred during high-intensity exercise where energy demand is high.
A powerlifter completes a 5-second maximal lift. Explain the predominant energy system being used and why it is suitable for this activity.
ATP-PC is predominant because the activity is short duration and maximal intensity. It rapidly resynthesises ATP using stored phosphocreatine without requiring oxygen.
A 400 m runner relies heavily on anaerobic glycolysis. Explain the advantages and disadvantages of this energy system for this event.
Advantages: rapid ATP production and does not require oxygen. Disadvantages: limited duration, lower ATP yield and accumulation of H+ causing fatigue.
Compare the ATP production rate and ATP yield of aerobic glycolysis compared with anaerobic glycolysis.
Anaerobic glycolysis has a faster ATP production rate but lower ATP yield. Aerobic glycolysis has a slower ATP production rate but produces a much greater total ATP yield.
Explain what happens to protein when it is used as an energy source.
Protein is broken into amino acids. The nitrogen component is removed through deamination and the remaining components can be used for energy or converted into glucose/fat.
Explain two limitations of the ATP-PC system during prolonged high-intensity exercise.
Limited stores of phosphocreatine mean it only provides energy for a short duration. It has a low ATP yield and requires recovery time to restore PC stores
Explain how the accumulation of hydrogen ions contributes to fatigue during high-intensity exercise.
H+ accumulation lowers muscle pH, interfering with enzyme activity and muscle contraction, contributing to fatigue and reduced force production.
Explain the role of oxygen during aerobic metabolism and why oxygen availability is important during prolonged exercise.
Oxygen allows the breakdown of fuels in the mitochondria to produce ATP efficiently. Limited oxygen availability increases reliance on anaerobic systems.
A cyclist completes a 4-hour race. Explain how fuel utilisation changes throughout the event and why.
Early stages rely more on carbohydrate because it provides ATP quickly. As duration increases, fat contribution increases because it provides a large energy store and helps conserve glycogen.