Exercise, Breathing, and Heart Rate – Analysis & Conclusions

How did exercise affect the time needed for the BTB solution to change color? Explain what BTB detects and why the color change occurred.

• Exercise decreased the time needed because BTB detects increased carbon dioxide, which forms carbonic acid, lowers pH, and turns the indicator yellow.

• Exercise increased the time needed because BTB detects rising oxygen levels.

• Exercise caused no change because BTB is a temperature indicator.

• Exercise decreased the time because BTB reacts only to lactic acid.

What can you conclude about the effect of exercise on the amount of carbon dioxide present in your exhaled breath? Why is this so?

• The amount of carbon dioxide in exhaled breath increases during exercise due to faster cellular respiration in working muscles.

• The amount of carbon dioxide decreases because muscles store carbon dioxide during exercise.

• The amount of carbon dioxide remains the same because respiration rate is independent of activity level.

• The amount of carbon dioxide increases because outside air contains more carbon dioxide during exercise.

What can you conclude about the effect of exercise on breathing rate? Why is this so?

• Breathing rate increases to deliver more oxygen and remove more carbon dioxide.

• Breathing rate decreases to conserve energy.

• Breathing rate remains unchanged because heart rate alone handles oxygen delivery.

• Breathing intermittently pauses to allow carbon dioxide to build up.

What can you conclude about the effect of exercise on heart rate? Why is this so, and what do your muscles need during exercise that the blood brings? Use the heart rate table showing higher averages after 1 minute (137.75 bpm) and 2 minutes (150.5 bpm) of exercise compared with resting averages (~92 bpm).

• Heart rate increases; blood brings oxygen and nutrients and removes carbon dioxide to meet muscular demand.

• Heart rate decreases; blood primarily brings heat to cool muscles.

• Heart rate is unchanged; blood mainly carries hormones that do not affect exercise demand.

• Heart rate increases; blood brings only water to muscles.

State whether your hypothesis was supported and explain what is happening in muscles as activity increases. Select all statements that correctly describe the physiology of increased muscle activity.

• Muscles need more oxygen to make ATP via cellular respiration when activity increases.

• Carbon dioxide production rises and must be removed more quickly.

• Increased activity decreases energy demand, so ATP use falls.

• Blood flow and heart rate increase to deliver oxygen and carry away wastes.

• Breathing slows down to conserve oxygen.

What happens to your heart rate when you exercise?

• 
• 
• It stays the same

Tags

NGSS.MS-PS3-5

What happens to your breathing rate when you exercise?

• It increases
• It decreases
• It stays the same

Tags

NGSS.HS-LS1-3

During exercise, what happens to the rate of breathing?

• It decreases

• It remains the same

• It increases

• It stops

Which of the following is a direct effect of exercise on the respiratory system?

• Decreased breathing rate

• Increased oxygen demand

• Decreased lung capacity

• Reduced carbon dioxide production

What is the effect of regular exercise on lung capacity over time?

• It decreases lung capacity

• It has no effect on lung capacity

• It increases lung capacity

• It damages the lungs