What are the 2 functions of the respiratory system?
1. gas exchange
2. acid-based balance
What are the 2 anatomical zones and what are their functions?
1. conducting zone
: bulk movement of gas
2. respiratory zone
: gas diffusion between conducting zone and blood
List the parts of the conducting zone from proximal to distal and identify which contain cart. and/or smooth muscle?
1. nasal cavity
3. larynx- cartilage
4. trachea- cartilage rings
5. bronchus- cartilage and smooth muscle
7. terminal bronchiole
Define epiglottis and location?
larynx > (cart. flap) covers airway during swallowing
Define glottis and location?
larynx > vocal folds and opening
distal functioning unit
> surrounded by cappillaries
List the processes that contribute to respiration?
2. external respiration
3. internal respiration
4. cellular respiration
bulk gas movement in/out of conducting zone
Define external respiration?
gas diffusion between alveolus and blood across the resp. membrane
Define internal respiration?
gas diffusion between blood and cells
Define cellular respiration?
oxidation of organic compounds to produce CO
purpose = ATP
What are the components of ventilation?
Which component of ventilation is (always) active and why?
inspiration d/t diaphragm contraction
* lung volume increases > pressure decreases
Which component of ventilation is passive and why?
expiration d/t diaphragm relax.
active (exercise and blockage)
* lung volume decreases > pressure increases
What type of compound is a surfactant?
What is a surfactant's function?
produced by alveolar epith. > decreases tention of water
What does a surfactant prevent?
Define tidal volume?
air inspired or expired (nl breath)
Define tidal capacity?
max air expired after max inspiration
Define partial pressure?
(P) pressure exerted by a gas in a mixture
Cite the rule that governs gas diffusion?
from high > low partial pressure
of other gases in the mixture
What are the correct pair of partial pressures that would promote diffusion of a specific gas from one location to another?
alveolus > PO
blood > PCO
How is most oxygen transported in the blood?
How is most carbon dioxide transported in the blood?
List the arterial PO
values with their corresponding % O
saturation of hemoglobin values and identify the significiance of each one?
a. 90 mm Hg= (97% O
b. 60 mm Hg:= (90%) PO
< 60--> large decrease in O
sat. (<60 = resp. failure)
c. 40mm Hg= (75%) symptoms
What stimulus does a central chemoreceptor respond to?
a normal person
How is ventilation rate affected in a central chemoreceptor (normal person)?
increase > rate increase
What is the major drive in a normal person?
What stimulus does a peripheral chemoreceptor respond to?
a person with COPD
How is the ventilation rate affected in a peripheral chemoreceptor (COPD)?
decrease > rate increase
What is the major drive in someone who retains CO
Which of these drives are more precise?