5b Function And Control Of Respiratory System Flashcards
What are the 4 distinct events that occur in respiration?
Pulmonary ventilation
External respiration
Internal respiration
Respiratory gas transport
Describe the first event of respiration.
Pulmonary ventilation: moving air into and out of the lungs, in essence, breathing
Describe the second event of respiration.
External respiration: Gas exchange between pulmonary blood ad alveoli
Describe the third event of respiration.
Internal respiration: gas exchange between tissue cells and blood in systemic capillaries
Describe the last step in respiration.
Respiratory gas transport: transport of oxygen and carbon dioxide via the bloodstream
What is the difference between internal and external respiration?
Internal respiration is the gas exchange that occurs within the tissues and cells inside in the body, specifically between systemic capillaries and tissue cells, whereas external respiration is the gas exchange that occurs between the oxygen poor blood and the external environment (between alveoli and alveolar capillaries )
What is the relationship between volume and pressure in terms of breathing?
The higher the volume, the lower the pressure and vice versa
Describe the mechanical process that makes pulmonary ventilation possible.
Changes in volume trigger changes in pressure, which lead to the movement of gases, particles, to equalize said pressure
What are the types of pressures that affect pulmonary ventilation? Briefly define
Intrapulmonary pressure: pressure inside alveoli
Intrapleural pressure: pressure inside pleural cavity
Atmospheric pressure: pressure of outside air
What is the intrapleural pressure with respect to the other pressures?
The intrapleural pressure should always be more negative than the other pressures
What are the phases of pulmonary ventilation?
Inspiration: air flows into the lungs
Expiration: air flows out of the lungs
What effect do the phases of pulmonary ventilation have on the intercostals?
Inspiration: contraction of the intercostals
Expiration: relaxing of the intercostals
Changes laterally
What is the pleural cavity?
Thin layer of serous fluid there to prevent friction between the lungs and the chest wall
Bordered by the visceral pleura (touching the lungs) and the parietal pleura (touching chest wall)
What role does the pleural cavity play in respiration?
Allows the lungs to expand when your chest expands
Why must the intrapleural pressure always be ore negative than the other pressures?
It allows for the alveoli/air sacs to open, acting like a vacuum or suction cup
What happens if the intrapleural pressure equals the atmospheric pressure?
Results in acelectasis, the lungs recoil and collapse
What can cause the intrapleural cavity to depressurize?
Opening the pleural cavity
Breaking the seal of the pleural membrane allows for the atmospheric air to enter, equalizing the pressure
What is the average total lung capacity?
6L
What is vital capacity and the average?
4.8 L
Amount of air that can move into and out of lungs (breathable air)
Given by: Vital capacity= TV+IRV+ERV
(Tidal volume, inspiration reserve volume, expiration reserve volume)
What is tidal volume and the average capacity?
Amount of air you exhale in a normal breathe, not exercising, at rest
0.5L
What is residual volume and the average?
The air you cant exhale, no matter how hard you try
1.2L
What is inspiratory reserve volume and the average?
Amount of air that can be taken in over the tidal volume
3.1L
What is the expiratory reserve volume and the average?
Amount of air that can be forcible exhaled after a tidal expiration
1.2 L
What are the key words to remember for external respiration?
Alveoli and alveolar capillaries