2.14 Exercise Flashcards
During exercise, what type of respiration do our bodies have to carry out more?
Cellular respiration
Why is more cellular respiration needed when doing exercise?
All exercise requires us to move our muscles much more than usual and any muscular contraction requires lots of energy from respiration
What do we have to increase in our bodies for more respiration when doing exercise? (2)
- Rate of breathing
- Volume of breaths
What are the downsides of increasing rate of breathing during exercise?
- It requires you to move the muscles around your lungs even more than usual which itself would require energy.
- We also need to pump this oxygen around the body (quicker than usual) so our heart rate would have to increase, which would require more energy.
What does the human body do with all the increased effort during exercise?
It means we can supply enough oxygen to all of our muscles to continue to use aerobic respiration
When would anaerobic respiration be used?
Sometimes when cycling or sprinting very fast, there won’t be enough oxygen to keep up with all of the demands, so our cells would have to start using anaerobic respiration.
Is anaerobic or aerobic respiration more efficient?
Aerobic
What is the main problem with anaerobic respiration?
It produces lactic acid as a product which will build up in our tissues and give a burning sensation in the muscles.
How does your body get rid of the build up lactic acid after anaerobic respiration?
- By reacting with oxygen - the more lactic acid that you’ve built up, the more oxygen needed. This is called an ‘oxygen debt’.
- For these reactions to take place, blood carries lactic acid from the muscles over to the liver, where it can react with oxygen and be converted back to glucose.
Describe how to investigate pulse rate (7)
1) Measure and record your pulse rate at rest.
2) Then do 3 minutes of gentle exercise, e.g. walking.
3) Measure and record your pulse rate again immediately after the exercise.
4) Then take regular measurements of your pulse rate until it has returned to its resting rate. Record the time that this takes - this is called the recovery rate.
5) Repeat steps 2-4 two more times now, but increase the intensity of the exercise each time (e.g. jog, then run).
6) Produce a bar chart of your results to show how pulse rate is affected by the intensity of the exercise. To reduce the effect of random errors on the results, collect anonymised results from a group of people and plot the average percentage change in pulse rate for each exercise. Do the same to show how recovery rate is affected by the intensity of exercise
7) Remember to control any variables during the experiment, e.g. if you’re using results from a group of people, make sure everyone’s done the same activities for the same length of time.
Scientists are able to investigate the link between regular exercise and a lower resting rate and faster recovery rate using long term studies. Describe how they would do this. (5)
1) Recruit a large number of volunteers that do not exercise regularly.
2) Record the resting heart rate for each volunteer, then ask the volunteers to all do the same exercise activity and record the recovery rate of each of the volunteers.
3) Split the group in half, and ask one group to continue with their normal lifestyle and the other group to exercise regularly for 3 months - e.g. take a brisk 30 minute walk, 5 times a week.
4) At the end of the trial period, ask the volunteers to come back and then repeat step 2.
5) Analyse the data.
Which type of respiration requires oxygen, aerobic or anaerobic?
Aerobic
Which type of respiration leads to an oxygen debt, aerobic or anaerobic?
Anaerobic respiration
Which organ in the body removes the lactic acid from the blood?
Liver
How do you measure a persons breathing rate?
Count how many times their chest rises and falls in a given amount of time
