Respiratory system

Question 1

How does exercise affect breathing rate?

Answer 1

• During exercise
• Chemoreceptors detect increased in acidity, CO2 level
• Baroreceptors detects increased in blood pressure
• Proprioceptors detects increased in muscle movement
• These information are sent to the respiratory control centre in the medulla oblongata
• RCC stimulates phrenic nerve
• Phrenic nerve increases the frequency and force of contraction of the diaphragm and respiratory muscle
• This causes faster and deeper breathing

Question 2

What is respiratory control?

Answer 2

Regulation of breathing rate

Question 3

Describe the mechanics of inspiration

Answer 3

1. Active
2. Diaphragm contracts
3. External intercostal muscles contract
4. Ribs move upwards and outwards
5. Volume of thoracic increases
6. Pressure decreases
7. Air move in

Question 4

Describe the mechanics of expiration

Answer 4

1. passive
2. Diaphragm relax
3. External intercostal muscles relax
4. Ribs move downwards and inwards
5. Volume of thoracic decreases
6. Pressure increases
7. Air is forced out

Question 5

What are the muscle that contracts during inspiration during exercise?

Answer 5

• Pectorals major
• Sternocledomastoid
• Scalene

Question 6

What are the muscle that contracts during expiration during exercise?

Answer 6

Internal intercostal muscle
Abdominals

Question 7

How does Bohr shift of haemoglobin affected by exercise?

Answer 7

• Curve shift to right
• Allow O2 to dissociate from HB more easily
• More O2 for aerobic respiration at working muscle

Question 8

What causes bohr shift?

Answer 8

• Increased CO2 level
• Increased acidity
• Increased temperature