Module 11 - Respiratory System Pt. 2 Physiology/ Application Flashcards
Ventilation, Gas Exchange, Gas Transport, Respiratory Centers
Breathing aka
ventilation
Air consists of
78% nitrogen
21% oxygen
1% carbon dioxide
Atmospheric pressure
force exerted on surfaces by molecules in air
At sea level atmospheric pressure is at
760mm Hg
Process of inspiration requires
muscles to contract & thoracic cavity expands
When the thoracic cavity size increases during inspiration, the pressure in the lungs
decreases
During inspiration the atmospheric pressure outside of the body is _____ than the inside of the lungs, so air is forced into the lungs
higher
Process of expiration requires
muscles to relax & thoracic cavity to contract
When the thoracic cavity size decreases during expiration, the pressure in the lungs
increases
During expiration the atmospheric pressure outside of the body is ____ than the inside of the lungs, so air is forced out of the lungs
lower
Gas exchange between the alveoli & blood capillaries is called
Alveolar gas exchange
During Alveolar gas exchange, _________ blood is carries from the ____ to the _____.
deoxygenated; heart; lungs
Blood vessels which transition from the pulmonary arteries to arterioles to capillaries that carry blood from the heart to the lungs is _____ in CO2 and ____ in O2
High; Low
During inspiration, air is delivered to the alveoli of the lungs. This inspired air is now ____ in CO2 & ____ in O2
Low; High
Partial pressure of oxygen being higher in alveoli than in the capillaries causes…
oxygen to diffuse across respiratory membrane from Alveoli to the capillaries
Partial pressure of carbon dioxide being higher in capillaries than in alveoli causes….
carbon dioxide to diffuse across respiratory membrane from capillaries to alveoli
Systemic gas exchange
throughout the tissues and blood vessels
Blood flowing to the tissues through systemic arteries & arterioles are ____ in O2 & ____ in CO2
High; Low
Systemic Cells have ____ CO2 & ____ O2 due to metabolism
High; Low
Partial pressure of oxygen being higher in the arterial end of systemic capillaries than in the systemic cells causes…
oxygen to diffuse out of the capillaries into the tissues,
Partial pressure of carbon dioxide being higher in the systemic cells & tissues than it is in the systemic capillaries causes…
carbon dioxide to diffuse from the tissues into the capillaries
Oxygen is transported by
hemoglobin & a small amount as a dissolved gas in plasma
Carbon dioxide is transported by
bicarbonate ions
Carbon dioxide that enters the blood combines with water and forms
carbonic acid
Carbonic acid dissociates and becomes
bicarbonate & hydrogen ions
Bicarbonate is transported through the blood vessels to the lungs where it combines with hydrogen to form
carbonic acid again, which dissociates back to carbon dioxide and water
Exact mechanism for setting rhythm of respiration is unknown. Breathing depends on stimuli of ____ ____ from the brain
skeletal muscles
Neurons in the ____ _____ & _____ control unconscious breathing
medulla oblongata & pons
Voluntary control is provided by our
motor cortex
Our unconscious breathing is controlled by 3 pairs of respiratory centers called
Dorsal respiratory group; Ventral respiratory group; Pneumotaxic center
The medullary rhythmicity center is found on the ____ _____ and contains the DRG & VRG.
medulla oblongata
Ventral respiratory group
sets rhythm of breathing (inspiration)
Dorsal respiratory group
modifies rate to adapt to varying conditions (inspiration)
Pneumotaxic center is found in the _____ & regulates what?
pons;
regulates shift from inspiration to expiration in quiet breathing
