Chapter 6 - Respiratory System Flashcards
Surfactant
Détergent that lowers surface tension and prevents the alveolus from collapsing on itself
Is the diaphragm under somatic or autonomic control?
Somatic
*breathing is autonomic
Total lung capacity
Maximum volume of air in lungs when one inhales completely
*usually 6 to 7 litres
Residual volume
Minimum volume of air in the lungs when one exhales completely
Vital capacity
Différence between air in the lungs when one exhales completely
VC = TLC - RV
Tidal volume
Volume of air inhaled or exhaled in normal breath
Expiratory reserve volume
Volume of additional air that can be forcibly exhaled after a normal exhalation
(EVR0
Inspiratory Réserve volume
Volume of additional air that can be forcibly inhaled after a normal inhalation
How is breathing regulated?
Neurons in medulla oblongata called ventilation center fire to cause contraction of the respiratory muscles
Neurons have chemoreceptors that are sensitive to CO2 concentration
What are some other uses of the lungs?
- thermoregulation
- immune function to prevent invaders from gaining access to bloodstream
How is heat regulated through the body surfaces?
Vasoconstriction and vasodilation
Lysozyme
Enzyme found in nasal cavity (and tears and saliva)
- attacks the peptidoglycan walls of gram-positive bacteria
What are some immune cells found in the lungs
Macrophages
Mast cells: have preformed antibodies on their surfaces
- cell releases inflammatory chemicals to promote immune response
Write out the bicarbonate buffer system equation
CO2 (g) + H20 (l) <=> H2CO3 (Aq) <=> H+ + HCO3-
Acidemia
Increased H+ concentration in blood
- chemoreceptors send signals to brain to increase resp rate
- ## CO2 blown off
