The Respiratory System Flashcards
Where are the lungs located?
thoracic cavity
What is the pathway that the air goes through in the respiratory system?
(1) Air enters through the external nares in the the nose
(2) Then it goes into the pharynx (food and air) and larynx (only air)
(3) Then it goes into the cartilaginous trachea and into one of two mainstem bronchi
(4) Then the air goes into bronchioles and then alveoli
What is the larynx?
the pathway below the pharynx that is just for air that leads into the lungs
What keeps food out of the larynx?
the epiglottis
What is surfactant?
a detergent that aveoli are coated in that lowers surface tension and keeps the aveoli from collapsing in on themselves
What is the pleurae?
membranes that surround the lungs and form a closed sac
What is the diaphragm?
a thin, muscular structure that divides the thoracic cavity from the abdominal cavity
What is intrapleural space?
the space between parietal and visceral pleaura and is filled with a thin layer of fluid
What is external intercostal muscle?
one of the layers of the muscle between the ribs to expand the thoracic cavity
How does inhalation work?
(1) Diaphragm flattens and the chest wall expands. The intrathoracic volume increases.
(2) Intrapleural volume increases. Intrapleural pressure decreases.
(3) Lungs expand into low pressure intrapleural space and its volume decreases.
(4) Air moves from high pressure outside space into the low pressure lungs
How does exhalation work?
(1) Diaphragm relaxes (or internal intercostal muscles are used to push it up) and the chest wall and lungs contract due to intrinsic elastic quality
(2) Volume in intrapleural decreases and pressure increases
(3) The pressure in intrapleural space/lungs is higher than outside
(4) Air is pushed out
What is a spirometer?
an instrument that a patient blows into and can measure the capacity of the lungs
What is TLC?
Total Lung Capacity - the maximum volume of air int he lungs when one inhales completely; usually around 6 or 7 liters
What is RV?
Residual Volume - the volume of air remaining in the lungs when one exhales completely
What is VC?
Vital Capacity - the difference between the minimum and maximum volume of air in the lungs (TLC-RV)
What is ERV?
Expiratory Reserve Volume - the volume of additional air that can be forcibly exhaled after a normal exhalation
What is IRV?
Inspiratory Reserve Volume - the volume of additional air that can be forcibly inhaled after a normal inhalation
What is the ventilation center?
a collection of neurons in the medulla oblongata that fire rhythmically to cause regular contraction of respiratory muscles
What is too much carbon dioxide in the blood called?
hypercarbia/hypercapnia
What is too low oxygen in the blood called?
hypoxemia
What is the relationship between VC, IRV, ERV and TV?
VC = IRV + ERV + TV
What are pulmonary arteries?
bring deoxygenated blood from the right ventricle to capillaries (inside the lungs)
What are pulmonary veins?
bring oxygenated blood from the lungs to the left atrium of the heart (inside the lungs)
How is the respiratory system used for thermoregulation?
Capillaries expand, more blood goes through, and more heat is released - cooling the body down OR
Capillaries restrict, less blood goes through, and heat is conserved - heating/maintaining the body
What are mast cells?
cells that have preformed antibodies on their surfaces, when pathogens attach the cell releases inflammatory chemicals into the surrounding area
How does the respiratory system deal with acidemia?
H+ increases —> CO2 increases —> respiratory rate increases —> CO2 concentration decreases —> H+ decreases —> pH decreases
How does the respiratory system deal with alkalemia?
too basic —> respiratory rate decreases —> CO2 concentration increases —> H+ increases —> pH increases
What is the bicarbonate buffer system?
CO2 (g) + H2O (l) H2CO3 (aq) H+ (aq) + HCO3- (aq)
Where are the vocal cords?
in the larynx
What is the respiratory system’s defense against pathogens?
(1) Nasal Cavity - lined with vibrissae hairs that trap particulates
(2) Lysozymes - attacks gram positive bacteria
(3) Mucus - trapped particulates and cilia in the tract push the mucus upwards (mucociliary escalator)