Respiratory System Flashcards
Which law governs pressure changes in ventilation?
Boyle’s law
This occurs when alveolar pressure falls below atmospheric pressure
Inhalation
2 muscles groups that contract to trigger inhalation
- Diaphragm
- External intercostals
3 accessory muscles used during forceful inhalation
- Sternocleidomastoids
- Scalenes
- Pectoralis minor
2 muscle groups involved in forceful exhalation
- Internal intercostals
- Abdominals
This decreases the effect of surface tensions exerted by alveolar fluid
Surfactant
The ease with which the lungs and thoracic wall can expand
Compliance
Another name for normal quiet breathing
Eupnea
Lung volumes and rate of respiration are measured with a…
Spirometer
6 things measure by spirometry
- Tidal volume
- Minute ventilation
- Alveolar ventilation rate
- Inspiratory reserve volume
- Expiratory reserve volume
- FEV1.0 (forced expiratory volume)
5 types of lung capacities
- Inspiratory
- Functional
- Residual
- Vital
- Total
Dalton’s law
Each gas in a mixture of gases exerts its own pressure as if all the other gases were not present
Henry’s law
The quantity of a gas that will dissolve in a liquid is proportional to the partial pressure of that gas and its solubility
External respiration (pulmonary gas exchange) is the exchange of gases between…
Alveoli and pulmonary blood capillaries
Internal respiration (systemic gas exchange) is the exchange of gases between…
Systemic blood capillaries and tissue cells
Percentages of 02 in oxygenated blood
- 1.5% dissolved in blood plasma
- 98.5% bound to haemoglobin as oxyhaemoglobin
5 things that affect the binding of 02 to haemoglobin
- P(O2)
- Acidity
- P(CO2)
- Temperature
- 2,3-bisphosphoglycerate (BPG)
Percentages of CO2 in deoxygenated blood
- 7% dissolved in blood plasma
- 23% combines with haemoglobin as carbaminohaemoglobin
- 70% is converted to HCO3-
Bohr effect
Haemoglobin’s affinity for O2 is lower, and O2 dissociates more readily from it, in the presence of CO2 and higher acidity
Haldane effect
In the presence of O2, less CO2 binds to haemoglobin
Respiratory centre is made of…
Medullary respiratory centre and pontine respiratory centre
Dorsal respiratory group of MRC controls…
Normal quiet breathing
Ventral respiratory group of MRC controls…
Rhythm and forceful breathing
Pontine respiratory centre modifies…
Rhythm of breathing during exercise, speaking and sleep
