Exercise

• What does your body do when you exercise to get enough energy to your cells?


  Your body responds in different ways to get enough energy to your cells.
• Why do muscles need energy from respiration during exercise?


  Muscles need energy from respiration to contract.
• What happens to respiration in your cells when you exercise?


  The increase in respiration means you need to get more oxygen into your cells.
• How does your body increase oxygen intake during exercise?

  Your breathing rate and breath volume increase to get more oxygen into the blood.
• What happens to your heart rate during exercise?


  Your heart rate increases to circulate oxygenated blood around the body faster.
• What is the effect of increased heart rate during exercise?


  It removes CO₂ more quickly from the body.
• What happens during vigorous exercise when oxygen supply is insufficient?


  Your muscles start respiring anaerobically.
• Why is anaerobic respiration not the best way to transfer energy from glucose?


  Because lactic acid builds up in the muscles, causing pain.
• What is muscle fatigue and when does it occur?

  Muscle fatigue occurs after long periods of exercise when muscles get tired and stop contracting efficiently.
• What is an "oxygen debt"?


  An oxygen debt is the amount of extra oxygen your body needs to react with the build-up of lactic acid.
• What happens to lactic acid after anaerobic respiration?


  Oxygen reacts with lactic acid to form harmless CO₂ and water.
• What must you do to "repay" the oxygen debt after exercising?


  You have to keep breathing hard for a while after you stop exercising.
• What happens to pulse and breathing rate after intense exercise?

  The pulse and breathing rate stay high while there are high levels of lactic acid and CO₂.
• How does the body cope with high levels of lactic acid?


  The blood transports lactic acid to the liver, where it is converted back to glucose.
• How can you measure breathing rate and heart rate during exercise?


  You can measure breathing rate by counting breaths and heart rate by taking the pulse.
• What is a method to investigate the effect of exercise on the body?


  • Take your pulse after:

  1. Sitting down for 5 minutes
  2. Gentle walking for 5 minutes
  3. Slow jogging for 5 minutes
  4. Running for 5 minutes

  • Plot results in a bar chart.
• What trend is observed in pulse rate with increasing exercise intensity?


  Your pulse rate will increase the more intense the exercise is.
• How can random errors be reduced when measuring pulse rates during exercise?


  • Conduct the experiment as a group.
  • Plot the average pulse rate for each exercise.
• Why do athletes breathe hard at the end of a sprinting race?


  To get rid of the lactic acid that’s built up in the muscles.
• What role does the liver play in dealing with lactic acid?


  The liver converts lactic acid back to glucose.
• What is the topic of the study material provided?

  Bioenergetics
• What type of exercise would likely lead to the highest concentration of lactic acid in the blood after 10 minutes?

  Vigorous exercise like sprinting.
• Why do exercise-bodies need to carry out more cellular respiration?


  To provide energy for muscle movement
• What is the relationship between exercise and muscular contraction?


  Muscular contraction requires a lot of energy during exercise
• How does exercise affect aerobic respiration?


  Exercise increases the need for aerobic respiration and oxygen
• What happens to heart rate during exercise?


  Heart rate increases
• What happens to breathing rate during exercise?


  Breathing rate increases
• What happens to breath volume during exercise?


  Breath volume increases
• What is oxygen debt?


  It is the extra oxygen needed to react with built-up lactic acid and remove it from cells
• What occurs during vigorous exercise regarding oxygen supply?


  Not enough oxygen is supplied to the muscles, leading to anaerobic respiration
• What builds up in muscles during anaerobic respiration?


  Lactic acid builds up in muscles
• What happens to heart rate and breathing rate after exercise?


  They stay high to repay oxygen debt
• How does blood help in dealing with lactic acid?


  Blood carries lactic acid from the muscles to the liver
• What happens to lactic acid in the liver?

  Lactic acid is converted to glucose
• What are the effects of exercise on the body?


  • More energy needed
  • More aerobic respiration needed
  • More oxygen needed
  • Increased heart rate
  • Increased breathing rate
  • Increased breath volume
• What is muscle fatigue and when does it occur?

  Muscle fatigue occurs during long periods of exercise when muscles get tired and stop contracting efficiently
• What is the method to measure breathing rate?


  Count how many times the chest rises and falls in one minute
• How can heart rate be measured?


  By measuring the pulse in the wrist or neck
• What is the role of the liver in relation to lactic acid?


  The liver converts lactic acid to glucose
• What are the key processes involved in oxygen debt and lactic acid management during exercise?

  1. Anaerobic respiration occurs due to insufficient oxygen
  2. Lactic acid builds up in muscles
  3. Oxygen debt is created
  4. Heart rate and breathing rate remain elevated post-exercise to repay oxygen debt
  5. Blood transports lactic acid to the liver for conversion to glucose