Respiratory Unit Lesson 2: Inspiration and Expiration Flashcards
what are the two phases of breathing
inspiration and expiration
what is the tidal volume
the volume inhaled and exhaled at rest (it is about 0.5L)
what is the inspiratory reserve volume
the amount of air that can be inhaled beyond the tidal volume(it is about 3.0L)
what is the expiratory reserve volume
the amount of air that can be exhaled beyond the tidal volume (it is about 1.5L)
what is the vital capacity
the maximum amount of air a person can inhale
what is residual volume
the volume of air remaining in the lungs after maximum forceful expiration (it is about 1L)
explain the process of inspiration
the diaphragm contracts which increases the total volume of thoracic cavity. this increase of thoracic volume causes the lungs to expand, which creates a partial vacuum as the air outside the lungs now has a higher pressure than the air inside the lungs. air then flows into the lungs
explain the process of expiration
the diaphragm relaxes, which creates a decrease in thoracic volume, causing the lungs to shrink in size. this change in volume causes air pressure to increase inside the body relative to outside the body. air is then expelled outside the body
what is the rate and frequency of breathing controlled by
the brain controls it in the respiratory centre found in the medulla oblongata
how does the respiratory centre regulate breathing
it automatically sends impulses to the diaphragm which causes it to contract
how do the levels of H+ and CO2 affect the rate of breathing
the respiratory centre is sensitive to those levels, and if either level rises, the rate of respiration is increased
how does O2 affect the rate of breathing(hint: talk about _____ bodies)
carotid and aortic bodies are sensitive to O2 levels. if these levels decrease, these bodies would send signals to the respiratory centre to increase the rate and depth of breathing
