Breathing and Oxygen

Question 1

What is breathing rate? (f)

Answer 1

Number of inspirations and expirations per minute

Question 2

What is tidal volume?

Answer 2

Volume of air inspired or expired per breath

Question 3

What is minute ventilation? (VE)

Answer 3

Volume of air inspired or expired per minute (product of f and TV)

Question 4

What is the correct order for pulmonary ventilation?

Answer 4

• MMVPA
• Muscle
• Movement
• Volume
• Pressure
• Air movement

Question 5

What type of breathing is passive?

Answer 5

Expiration at rest

Question 6

What changes happen to inspiration during exercise?

Answer 6

• More dramatic, stronger contractions

- More muscles recruited

Question 7

What are the additional inspiratory muscles?

Answer 7

• Sternocleidomastoid

- Pectoralis minor

Question 8

What changes happen to expiration during exercise?

Answer 8

• Becomes an active process

- Additional expiratory muscles recruited

Question 9

What are the additional expiratory muscles?

Answer 9

• Internal intercostals

- Rectus abdominis

Question 10

What centre is ventilation controlled by?

Answer 10

RCC (respiratory control centre)

Question 11

What are the normal inspiratory muscles?

Answer 11

• External intercostals

- Diaphragm

Question 12

What is the process of respiratory control?

Answer 12

• Receptor Feedback
• RCC
• Action

Question 13

What are the elements of the RCC?

Answer 13

• Inspiratory centre

- Expiratory centre (inactive at rest)

Question 14

What nerves and muscles are active in ventilation at rest?

Answer 14

• Intercostal nerve stimulates external intercostals

- Phrenic nerve stimulates the diaphragm

Question 15

What receptors are used by the Inspiratory CC?

Answer 15

• Chemoreceptors (CO2 in air)
• Proprioceptors (movement at lungs)
• Thermoreceptors (higher temperature)

Question 16

What receptors are used by the Expiratory CC?

Answer 16

• Baroreceptors (detect tissue stretch)

Question 17

What changes occur at the muscles during exercise?

Answer 17

• PO2 decreases

- PCO2 increases

Question 18

What does the change in gas pressure at muscles during exercise cause?

Answer 18

Steeper diffusion gradient means more diffusion takes place

Question 19

What is the role of haemoglobin and myoglobin?

Answer 19

Oxygen binding proteins. Myoglobin is in the blood and has a higher affinity

Question 20

What is the saturation of blood leaving the lungs?

Answer 20

Always 100%

Question 21

What changes in terms of saturation during exercise?

Answer 21

At rest, only around 25% of oxygen is dissociated at the muscles, increasing to 75% during exercise

Question 22

What impacts on haemoglobin’s O2 affinity?

Answer 22

• Partial pressure of O2 (High means affinity)
• Partial pressure CO2 (Low means affinity)
• Acidity (Acidic means low affinity)
• Temperature (High temp means low affinity)

Question 23

What is the Bohr Shift?

Answer 23

A right shift in the oxygen dissociation curve due to acidity, CO2, temperature, O2 levels at muscles. More oxygen is dossociated at intense levels of exercise