Respiratory System Part II Flashcards
Expiration
process that moves air out of lungs
true or false: during expiration intra-alveolar pressure > atmospheric pressure?
true
true or false: resting expiration is a passive process
true
process of resting expiration
- diaphragm and external intercostals relax
- Thoracic cavity and lungs return to original size
Who aids the lungs in the process of inspiration and expiration?
elastic tissue in lungs and thoracic wall
What happens during resting expiration?
lung volume decreases
intra-alveolar pressure increases to +1 cm of H2O (pushes air out)
True or false: air outflow continues until both pressures are equal
true
Forceful expiration requires muscle contraction:
- intercostal muscles (depress and retract the ribs)
- abdominal muscles (force abdominal viscera and diaphragm upward)
True or False: muscle contraction further decreases volume of the thoracic cavity and lungs
true; causing a greater increase in intra-alveolar pressure, causing more air to flow out.
In a healthy adult number of breathing cycles per min?
12- 15
breathing cycle
one inspiration followed by one expiration
True or false: volume of air inhaled and exhaled during resting and forceful breathing cycle varies?
true
factors that affect breathing cycle
- size
- age
- sex
- physical condtion
true or false: volumes 80% or less than healthy range indicate pulmonary disease
true
spirometers
used to determine respiratory volume
spirogram
graphic record of air volume being exchanged
Tidal Volume (VT)
volume of air exchanged (inhaled or exhaled) during a resting breathing cycle.
Normal tidal volume
500 mL
Inspiratory reserve volume (IRV)
max. volume of air that can be forcefully inhaled after tidal inspiration
normal inspiration reserve volume
3,000 mL
Expiratory Reserve Volume (ERV)
Max. volume of air forcefully exhaled after tidal expiration
normal expiration reserve volume
1,100 mL
Residual Volume (RV)
volume of air in lungs after expelling ERV
normal residual volume
1,200 mL
True or False: residual volume exists because of intrapleural pressure and surfactant
true
True or false: respiration capacities can be calculated by the summation of 2 or more respiratory volumes.
true
Vital capacity (VT + IRV + ERV)
max. amount of air that can be exchanged
normal vital capacity (VC)
4,600 mL
total lung capacity (TLC)
VC+ RV
normal value for total lung capacity
5,800 mL
Centers for involuntary control of breathing are located
medulla oblongata and pons
Who controls voluntary override of breathing?
primary motor area of cerebral cortex
Respiratory Rhythmicity Center
2 bilateral groups of neurons in the medulla oblongata
Groups of Respiratory Rhythmicity Center
- Ventral Respiratory Group
- Dorsal Respiratory Group
Ventral Respiratory Group
responsible for normal rhythmic cycle of breathing (inspiration and expiration) ;
The neurons in Ventral Respiratory Group send action potentials to _____ and _____ .
diaphragm and external intercostalsl; causing them to contract