The lungs Flashcards
Explain the route air must take when it is inhaled, from the nose to the alveoli
Comes in through nasal nares, enters pharynx, then the larynx, then the trachea, then goes into either the left or right bronchi, which branches into bronchioles, and then finally ends in the alveoli
This process is active and involves contraction of muscles, the most important of which is the diaphragm
Inhalation
This process is passive and involves the relaxation of muscles
Exhalation
The pressure difference between the parietal pleura and the visceral pleura is what drives this fundamental process
Breathing
The parietal pleura is located ____ while the visceral pleura is located _____, with the interpleural space between them
Outside
Inside
How does the medulla oblongata help with maintaining respiratory regulation?
The medulla oblongata contains sensitive receptors that monitor the [CO2], which then changes breathing in order to alter than concentration. It also has receptors to monitor O2 levels during hypoxia
How do the capillaries and alveoli work together to perform gas exchange?
The alveoli are surrounded by capillaries that bring in deoxygenated blood from the pulmonary artery, so the alveoli takes CO2 out of that blood and replaces it with O2. The blood then travels to the pulmonary vein and to the heart to be cirulated
How does vasoconstriction or vasodilation help with thermoregulation?
Dilating the blood vessels allows for more blood to pass through, which increases the thermal energy being circulated. Similarly, if the vessels are constricted, the body will cool down bc less blood is getting through as quickly
How does the respiratory system help with immune defense?
Hair in the nasal cavity and enzymes called lysozymes that trap/lyse bacteria are able to prevent things from getting inside the body
Inside the lungs, macrophages identify, trap and alert other immune cells to the presence of invaders
Mast cells have preformed antibodies that release signals when pathogens bind to them (these are the cells that respond to allergies)
How is the respiratory system able to control the pH buffer?
Since the pH buffer is based on concentrations of CO2, HCO3-, H+, H2CO3, if one of those is out of balance and causing a slight pH change, the body will alter breathing to maintain equilibrium.
Ex: if there’s a low pH (acidemia) breathing increases, in order to increase the amount of CO2 in the blood and decrease H+
If there’s a high pH (alkalemia) breathing slows down to decrease the amount of CO2 coming in
Refers to the volume of air that can be forcibly inhaled after a normal inhalation
Inspiratory reserve volume
Refers to the volume of air that can be forcibly exhaled after a normal exhalation
Expiratory reserve volume
Refers to the max capacity of the lungs on a complete inhale
Total lung capacity
Refers to the volume of air left after an exhale
Residual volume
Refers to the difference between the maximum air capacity and the minimum air capacity
Vital capacity
