Breathing Process Flashcards
What is the major function of the respiratory system?
To supply the body with oxygen and to dispose of carbon dioxide.
What do you understand by pulmonary ventilation?
It is the act of breathing, which can be described as the movement of air into and out of the lungs.
What are the major mechanisms that drive pulmonary ventilation?
Atmospheric pressure(Patm)
Alveolar pressure(Palv)
Intrapleural pressure(Pip)
What is alveolar pressure?
Air pressure within the alveoli.
What is intrapleural pressure?
The pressure of air within the pleural cavity, between the visceral and parietal pleurae.
The ability to breath is __________ on the air pressure of the ___________ and the air pressure within the _______.
dependent; atmosphere; lungs
What are the 3 types of pressure that pulmonary ventilation is dependent on?
- Atmospheric pressure
- Intra-alveolar pressure
- Interpleural pressure
What is atmospheric pressure?
It is the amount of force that is exerted by gases in the air surrounding any given surface such as the body.
Note:- Atmospheric pressure can be expressed in terms of the unit atmosphere abbreviated atm or in millimetres of mercury(mm Hg).
-One atm= 760 mm Hg(atmospheric pressure at sea level).
What is intra-alveolar pressure?
It is the pressure of air within the alveoli which changes during the different phases of breathing.
What causes the parietal pleura and visceral pleura to adhere to one another?
A thin layer of serous fluid.
Intrapleural pressure is always lower than or negative to the ____________ pressure.
intra-alveolar
Which cells closely monitor the intrapleural pressure?
Mesothelial cells
What is transpulmonary pressure?
It is the difference between the intrapleural and intra-alveolar pressures and it determines the size of the lungs.
Note: A higher transpulmonary pressure corresponds to a larger lung.
What are the physical factors affecting pulmonary ventilation?
Surface tension of the Alveolar fluid.
Compliance of the lungs.
Airway resistance
What do you understand by thoracic wall compliance?
It is the ability of the thoracic wall to stretch under pressure.
What is pulmonary ventilation?
It is a mechanical process that depends on volume changes in the thoracic cavity.
Pulmonary ventilation comprises of two major steps: __________ and __________.
inspiration ; expiration
Explain the inspiration process?
It is a process that causes air to enter the lungs.
Explain the expiration process?
It is a process that causes air to leave the lungs.
What can be considered as a respiratory cycle?
One sequence of inspiration and expiration.
What are the two muscle groups that are used during normal respiration?
Diaphragm and external intercostal muscles.
What happens when the diaphragm contracts?
It moves inferiorly toward the abdominal cavity, creating a larger thoracic cavity and more space for the lungs.
What happens when the external intercostal muscles contracts?
The ribs are going to move upward and outward, causing the rib cage to expand which increases the volume of the thoracic cavity.
Why is it said that the process of normal respiration is passive?
It means that energy is not required to push air out of the lungs.
Give the different types of breathing?
- Quiet breathing(Eupnoea)
- A deep breath(Diaphragmatic breathing)
- A shallow breath(Costal breathing)
- Forced breathing(hyperpnea)
Describe eupnoea(quiet breathing)?
It is a mode of breathing that occurs at rest and does not require the cognitive thought of the individual.
Describe hyperpnea(forced breathing)?
It is a mode of breathing that can occur during exercise or actions that require the active manipulation of breathing. (e.g Singing)
