Respiratory Flashcards
Respiration refers to two related processes.
- External respiration - includes all the processes involved in the exchange of O2 and CO2 in the pulmonary blood and alveoli. The purpose is to meet the demands of cells.
- Internal respiration - the absorption of O2 and the release of CO2 by cells. It occurs at systemic capillaries where gas exchange takes place between the blood and body cells.
Respiration refers to two related processes.
- External respiration - includes all the processes involved in the exchange of O2 and CO2 in the pulmonary blood and alveoli. The purpose is to meet the demands of cells.
- Internal respiration - the absorption of O2 and the release of CO2 by cells. It occurs at systemic capillaries where gas exchange takes place between the blood and body cells.
Respiration that includes all the processes involved in the exchange of O2 and CO2 in the pulmonary blood and alveoli. The purpose is to meet the demands of cells. Gas exchanges are being made between the blood and body exterior.
External respiration
Respiration that involves the absorption of O2 and the release of CO2 by cells. It occurs at systemic capillaries where gas exchange takes place between the blood and body cells. Gas exchange between blood and cells inside the body.
Internal respiration
External respiration involves three integrated steps
i. Pulmonary ventilation (or Breathing), which involves the physical movement of air into and out of the lungs
ii. Gas diffusion across the respiratory membrane between alveolar air spaces and alveolar capillaries, and across capillary walls between blood and other tissues.
iii. The transport of O2 and CO2 between alveolar capillaries and capillary beds in other tissues.
If the supply of oxygen to tissue is low the condition is called _____. If the supply is cut off completely, the condition is called ____. This kills cells very quickly.
hypoxia/anoxia
BREATHING. Air must move into and out of the lungs so that gases in the alveoli are continuously refreshed. It prevents the build up of carbon dioxide in the alveoli and ensure adequate oxygen for the bloodstream. It is the movement of air into and out of the respiratory tract cycles between pressure below atmospheric pressures and pressure above atmospheric pressure. The cycle is explained by Boyle’s Law.
Pulmonary ventilation
Primary function of pulmonary ventilation.
maintenance of adequate alveolar ventilation – movement of air into and out of the alveoli.
- AS PRESSURE INCREASE, VOLUME DECREASE.
For a gas in a closed container, the pressure of the gas varies inversely to the volume, if the temperature of the gas is held constant.
Boyle’s law
Boyle’s Laws says that:
In a closed container, if the volume of the container increases, the air pressure in the container ____ (assuming remains temperature constant)
falls
Boyle’s Laws says that:
If the volume of the container decreases the pressure of the air in the container ____.
increases
Boyle’s Laws says that:
Air will flow from an area of ______ to an area of lower pressure.
high pressure
Boyle’s law formula.
Pressure α 1/V (T is held constant)
A single respiratory cycle consists of ____ and _____.
inspiration and expiration
In ______, the lung volume increases and the pressure in the lung falls. Hence atmospheric air (which is at a higher pressure than alveolar air) rushes into the lung.
inspiration
In ______, the volume of the lungs decreases, hence the alveolar pressure rises and becomes higher than atmospheric pressure and so alveolar air moves out of the lung.
expiration
The pressure inside the alveoli.
Intrapulmonary pressure
Intapulmonary cycle.
a. At the start of the respiratory cycle, the intrapulmonary pressure and the atmospheric pressure are equal and no air is moving.
b. When inspiration (inhalation) begins the pressure drops to about -6mm Hg and the average intrapulmonary pressure is 760 mm-1 mmHg ( i.e. 759 mm Hg).
c. On expiration (exhalation) the intrapulmonary pressure is 760 mm Hg + 1 mmHg (i.e., 761 mmHg)
d. The amount of air moved in to the lung during inhalation is equal to the amount that moves out on exhalation. That amount is called the tidal volume.
a. At the start of the respiratory cycle, the intrapulmonary pressure and the _______ pressure are equal and no air is moving.
atmospheric pressure
b. When inspiration (inhalation) begins the pressure drops to about -6mm Hg and the average intrapulmonary pressure is _______ mm - 1 mmHg.
760 mm - 1 mmHg ( i.e. 759 mm Hg).
c. On expiration (exhalation) the intrapulmonary pressure is _____ mm + 1 mmHg.
760 mm Hg + 1 mmHg (i.e., 761 mmHg)
d. The amount of air moved in to the lung during inhalation is equal to the amount that moves out on exhalation. That amount is called the ________.
tidal volume
During ______, pressure change such as 760 -30 mm Hg ( 730 mmHg) at inhalation and 760 + 100mm Hg (860 mmHg) can occur.
heavy breathing
Changes in volume of the thoracic cavity is due to (4)
i. contraction and relaxation of the diaphragm
ii. articulation(jointed) between the ribs and the vertebrae
iii. movement of the rib cage
iv. contraction and relaxation of the intercostals muscles