Respiratory system

Question 1

What is minute ventilation (VE), and how is it calculated?

Answer 1

The amount of air moved in and out of the lungs in one minute
VE = Respiratory rate (breaths pmin) x Tidal volume

Question 2

How do oxygen and carbon dioxide pressures change during exercise?

Answer 2

Oxygen in the muscle cell drops
Carbon dioxide in the muscle cell rises

Oxygen in the alveoli increases
Carbon dioxide in the capillary increases slightly

Question 3

What are the effects of smoking on the respiratory system?

Answer 3

• Smoke damages the cilia (tiny hairs that sweep away debris to keep the airways clear)
• Damaged cilia cause excess mucus which clogs the bronchial space
• The alveoli gets damaged and loses its effectiveness at transferring oxygen to the blood
• Carbon monoxide binds to haemoglobin rather than oxygen