CONTENTS
PULMONARY VENTILATION 1
MECHANICS OF BREATHING 3
GAS EXCHANGE IN LUNGS 4
BLOOD GAS TRANSPORT 7
NEURAL CONTROL OF BREATHING 10
INTEGRATED CONTROL OF BREATHING 13
PULMONARY DEFENCE MECHANISMS 15
PATHOPHYSIOLOGY OF ASTHMA 17
PHYSIOLOGY:
PATHOPHYSIOLOGY OF COPD 19
RESPIRATORY SYSTEM AIRWAY PHARMACOLOGY 21
Revision Question Bank Biomedical Science Sem 2
,SGUL HINDU SOCIETY 1
PULMONARY VENTILATION
1. Why do we need to respiratory system? • Cells require energy to function, we need
oxygen to make this energy
• Atmosphere is a source of oxygen
• Our bodies are too large to solely rely on simple
diffusion of gases
2. What are the primary functions of the • To supply respiring tissues with oxygen and to
respiratory system? remove carbon dioxide
• Gas exchange relies on partial pressure
gradients between alveolar air and blood
• To maintain gradients of O2 and CO2 by
ventilating gas exchange surfaces
• Acid-base balance of body
• Communication and metabolism
3. What 3 things does the upper respiratory tract • Nasal cavity
consist of? • Paranasal sinuses
• Carina of trachea
4. Why is pulmonary ventilation required? • To maintain adequate O2 supply to respiring
tissues
• To maintain O2 and CO2 gradients between
alveolar air and arterial blood
5. What does changing metabolic demands • Different levels of gas exchange
require? • Change the rate of alveolar ventilation to
modulate the partial pressure gradients
between alveoli and blood
6. What is hypoventilation? • Results in excessive levels of CO2 in arterial
blood
• Ventilation decreases
• Partial pressure of CO2 increases
• Alveolar O2 pressure increases
7. What is hyperventilation? • Results in reduced levels of CO2 in arterial blood
• Ventilation increases
• Partial pressure of CO2 decreases
• Alveolar O2 pressure increases
8. What is total ventilation? • The volume of fresh air entering the respiratory
system per unit time
9. What does ventilation depend on? Give the • Volume
equation that corresponds to this. • Rate of breathing
• V=VT x f
• V = minute volume
• VT= tidal volume
• f = frequency
10. Why is alveolar air not the same as inspired air? • As the respiratory system is a 2-way system – air
enters the same path it leaves in
• The lungs contain a mixture of stale and fresh
air
• A residual volume of air remains in the airway
and lungs at the end of expiration
• There is dead space volume – the volume of air
that doesn’t reach the alveoli or takes place in
gas exchange
11. What is the equation for calculating alveolar • VA=(VT-VD) x f
ventilation? • VA = alveolar minute volume
• VT-VD = volume of fresh air entering alveoli
• VD=dead space volume
, SGUL HINDU SOCIETY 2
12. How does the respiratory system achieve • Gases move from connected areas of higher
movement of air? pressure to lower pressure, down a pressure
gradient
• This occurs until equilibrium is re-established
13. What is Boyle’s Law? • PV=nRT
• Pressure and volume are inversely proportional
• The ideal gas law
14. How does breathing work? Refer to changes in • Changes in lung volume induce changes in
lung volume and alveolar pressure. alveolar pressure
• This generates pressure gradients between
alveoli and atmosphere, causing air to flow
• INSPIRATION:
- air enters the lungs as the alveolar pressure is
less than the atmospheric pressure
- thoracic cavity expands
- alveolar pressure decreases
• EXPIRATION:
- air leaves the lungs as the alveolar pressure is
greater than the atmospheric pressure
- thoracic cavity volume decreases
- alveolar pressure increases
15. How are the lungs and chest wall related? • Indirectly attached via the pleural cavity
16. Describe the pleural cavity • It is the fluid filled space between the
membranes that line the chest wall and each
lung
• It helps to reduce friction between the
membranes
• Resists changes in volume
• Opposing elastic recoil of chest wall and lungs
results in sub-atmospheric pressure within the
pleural cavity
17. What are the 2 types of pleura? • VISCERAL PLEURA: inner pleura, lines each lung
• PARIETAL PLEURA: outer pleura, lines thoracic
cavity
18. Explain the mechanics for inspiration • Diaphragm contracts
• Volume of thoracic cavity increases
• External intercostal muscles contract
• Internal intercostal muscles relax
• Intrapleural pressure becomes more negative
• Lungs expand, increasing volume
• Alveolar pressure lower than atmospheric
pressure
19. Explain the mechanics for expiration • Diaphragm relaxes
• Volume of thoracic cavity decreases
• External intercostal muscles relax
• Internal intercostal muscles contract
• Intrapleural pressure becomes less negative
• Lungs compressed, decreasing volume
• Alveolar pressure high than atmospheric
pressure
20. What occurs if either pleura is ruptured? • Pneumothorax
• Pressure gradient between pleural cavity and
atmosphere causes air to enter the pleural
cavity
• There is a loss of negative intrapleural pressure
• Lung tissue collapses, due to elastic recoil
concept
PULMONARY VENTILATION 1
MECHANICS OF BREATHING 3
GAS EXCHANGE IN LUNGS 4
BLOOD GAS TRANSPORT 7
NEURAL CONTROL OF BREATHING 10
INTEGRATED CONTROL OF BREATHING 13
PULMONARY DEFENCE MECHANISMS 15
PATHOPHYSIOLOGY OF ASTHMA 17
PHYSIOLOGY:
PATHOPHYSIOLOGY OF COPD 19
RESPIRATORY SYSTEM AIRWAY PHARMACOLOGY 21
Revision Question Bank Biomedical Science Sem 2
,SGUL HINDU SOCIETY 1
PULMONARY VENTILATION
1. Why do we need to respiratory system? • Cells require energy to function, we need
oxygen to make this energy
• Atmosphere is a source of oxygen
• Our bodies are too large to solely rely on simple
diffusion of gases
2. What are the primary functions of the • To supply respiring tissues with oxygen and to
respiratory system? remove carbon dioxide
• Gas exchange relies on partial pressure
gradients between alveolar air and blood
• To maintain gradients of O2 and CO2 by
ventilating gas exchange surfaces
• Acid-base balance of body
• Communication and metabolism
3. What 3 things does the upper respiratory tract • Nasal cavity
consist of? • Paranasal sinuses
• Carina of trachea
4. Why is pulmonary ventilation required? • To maintain adequate O2 supply to respiring
tissues
• To maintain O2 and CO2 gradients between
alveolar air and arterial blood
5. What does changing metabolic demands • Different levels of gas exchange
require? • Change the rate of alveolar ventilation to
modulate the partial pressure gradients
between alveoli and blood
6. What is hypoventilation? • Results in excessive levels of CO2 in arterial
blood
• Ventilation decreases
• Partial pressure of CO2 increases
• Alveolar O2 pressure increases
7. What is hyperventilation? • Results in reduced levels of CO2 in arterial blood
• Ventilation increases
• Partial pressure of CO2 decreases
• Alveolar O2 pressure increases
8. What is total ventilation? • The volume of fresh air entering the respiratory
system per unit time
9. What does ventilation depend on? Give the • Volume
equation that corresponds to this. • Rate of breathing
• V=VT x f
• V = minute volume
• VT= tidal volume
• f = frequency
10. Why is alveolar air not the same as inspired air? • As the respiratory system is a 2-way system – air
enters the same path it leaves in
• The lungs contain a mixture of stale and fresh
air
• A residual volume of air remains in the airway
and lungs at the end of expiration
• There is dead space volume – the volume of air
that doesn’t reach the alveoli or takes place in
gas exchange
11. What is the equation for calculating alveolar • VA=(VT-VD) x f
ventilation? • VA = alveolar minute volume
• VT-VD = volume of fresh air entering alveoli
• VD=dead space volume
, SGUL HINDU SOCIETY 2
12. How does the respiratory system achieve • Gases move from connected areas of higher
movement of air? pressure to lower pressure, down a pressure
gradient
• This occurs until equilibrium is re-established
13. What is Boyle’s Law? • PV=nRT
• Pressure and volume are inversely proportional
• The ideal gas law
14. How does breathing work? Refer to changes in • Changes in lung volume induce changes in
lung volume and alveolar pressure. alveolar pressure
• This generates pressure gradients between
alveoli and atmosphere, causing air to flow
• INSPIRATION:
- air enters the lungs as the alveolar pressure is
less than the atmospheric pressure
- thoracic cavity expands
- alveolar pressure decreases
• EXPIRATION:
- air leaves the lungs as the alveolar pressure is
greater than the atmospheric pressure
- thoracic cavity volume decreases
- alveolar pressure increases
15. How are the lungs and chest wall related? • Indirectly attached via the pleural cavity
16. Describe the pleural cavity • It is the fluid filled space between the
membranes that line the chest wall and each
lung
• It helps to reduce friction between the
membranes
• Resists changes in volume
• Opposing elastic recoil of chest wall and lungs
results in sub-atmospheric pressure within the
pleural cavity
17. What are the 2 types of pleura? • VISCERAL PLEURA: inner pleura, lines each lung
• PARIETAL PLEURA: outer pleura, lines thoracic
cavity
18. Explain the mechanics for inspiration • Diaphragm contracts
• Volume of thoracic cavity increases
• External intercostal muscles contract
• Internal intercostal muscles relax
• Intrapleural pressure becomes more negative
• Lungs expand, increasing volume
• Alveolar pressure lower than atmospheric
pressure
19. Explain the mechanics for expiration • Diaphragm relaxes
• Volume of thoracic cavity decreases
• External intercostal muscles relax
• Internal intercostal muscles contract
• Intrapleural pressure becomes less negative
• Lungs compressed, decreasing volume
• Alveolar pressure high than atmospheric
pressure
20. What occurs if either pleura is ruptured? • Pneumothorax
• Pressure gradient between pleural cavity and
atmosphere causes air to enter the pleural
cavity
• There is a loss of negative intrapleural pressure
• Lung tissue collapses, due to elastic recoil
concept
