L15 Flashcards
List the four basic functions of the respiratory system
- Exchange of gas between the atmosphere and blood
- Homeostatic regulation of body pH, ability to bind O2 and CO2
- Protection from inhaled pathogens and irritating substances
- Vocalization
What are the characteristics of respiratory bulk flow?
- Flow takes place from high to Low pressure
- muscular pump creates pressure gradients
- resistance to airflow is is influenced primarily by diameter of tubes where air flows
What is cellular respiration?
This is the intracellular reaction of O2 with organic molecules to produce Co2, H2O and ATP
What are the four steps for external respiration?
- Exchange of air between atmosphere and lungs is inspiration and expiration
- Exchange of O2 and Co2 between lungs and blood
- Transport of O2 and Co2 by blood
- Exchange of gases between blood and cells
What are the three respiratory systems structures and functions?
- Conducting system/airways- this has upper and lower respiratory tracts (upper= mouth, basal cavity, pharynx, larynx. Lower= trachea, primary brochi, branches, lungs)
- Alveoli site of gas exchange (respiratory zone)
- Thoracic cage (bones, muscles, spine, ands rib cage)
What is the pleural sac of the lungs?
- this encloses the lungs, pleura (which contains a layer or elastic and connective tissue with capillaries)
- has pleural fluids which lower friction between membranes an holds lungs tight against wall
- this forms a double membrane surrounding the lungs similar to a fluid filled ballon surrounding an air filled ballon
Branching bronchi and more bronchi have a ______ effect on exchange
Greater
Name the simple pathway of airway
Pharynx—>larynx—>trachea—>primary bronchi—>bronchioles
Larynx contain vocal cords
The airway is warm and humid and filters air, list three factors that the airway also provides to air
- Warming air to body temperature
- Adding water vapour
- Filtering foreign material
_____ cells line airway and _____ glands secrete saline and mucus
Epithelial, submucosal
Cells have ___ which move the mucus layer towards the pharynx and removes trapped pathogens and particles
Cilia
Name the four steps in the model of saline secretion by airway epithelial
- NKCC brings CL into epithelial cell from ECF (NKCC- Na, K, -2CL)
- Apial Anion channels induce CFTR allowing CL to enter lumen (cysticfiberous transmembrane)
- Na+ goes from ECF to lumen by paracellular pathway, drawn by electrochemical gradient
- NaCl moves from ECF to lumen creating a [gradient] so water flowers to lumen
Why cant thick fluids be easily moved?
Due to the build up or lack of mucus, this causes mucus to trap pathogens which stay in place
Alveoli are sites of gas exchange, what are the type types of alveoli?
Type I- gas exchange (these are vast majority of cells)
Type II- produce surfactants (it helps with stretching of airways. Needs collagen and elastic tissues)
Connective tissues in alveoli are elastic which allow for _______ and collagen which allow for ______
Airway stretch, support
Type II alveoli cells have a close association between what?
Capillaries
Low resistance is due to _______
Fewer blood vessels
Explain some characteristics of gas laws
Atmospheric pressure and environment air pressure is 760mm Hg
- this decreases with altitude (gas moves down pressure gradient)
- increases underwater (air is a mixture of gases)
- in respiratory system, air is not set at 760mm Hg but 0.
What is Dalton’s law?
Total pressure equals the sum of all partial pressures
What is Boyles Law?
As pressure decreases, volume increases
As pressure increases, volume decreases
When air is moved through a conducting zone, how much of it is humidified?
100%
What is the ideal gas equation? What do the constants mean? If this were to be applied to human respiratory function, what does the equation become?
P=nRT
(P=pressure, N=moles of gas, V=Volume, R=gas constant, T=Temperature)
In humans, this would be V=1/P since moles and temperature are constant and pressure and volume have an inverse relationship
What does a spirometer tell you?
If values from the spirometer are not in a specific range, they can predict respiratory issues
Explain the types of volumes below:
vT
IRV
ERV
RV
Tidal volume (vT) is volume that moves during a respiratory cycle
Inspiratory reserve volume (IRV) is the additional volume above vT
Expiratory reserve volume (ERV) forcefully exhaled after end of normal respiration
Residual volume (RV) is volume of air in system after max exhale
Explain the type of lung capacities below:
VC
TLC
IC
FRC
Vital capacity= IRV+ERV+vT
Total Lung Capacity= IRV+ERV+vT+RV
Inspiratory capacity= vT+IRV
Functional Reserve Capacity= ERV+RV
What are obstructive pulmonary diseases?
- these are associated with an increased airway resistance, the residual volume increases and its harder to inhale and exhale
- FRC increases
- VC decreases
- examples: brochitus, emphysema, asthma
What are restricted pulmonary diseases?
-more difficult for lungs to expand
-TLC decreases
-VC decreases
Examples: pulmonary fibrosis, sarcoidosis
What is forced vital capacity (FVC)?
- this is the maximum volume inhalation followed by exhalation as fast as possible
- low FVC indicates restrictive pulmonary diseases
What is Forced Expiratory Volume (FEV)?
This is the percentage of FVC that can be exhaled in one second
- normal FEV= 80%
- FEV < 80% is obstructive pulmonary diseases
If FVC is normal and FEV is reduced, what does this mean
Obstructive pulmonary diseases
If FVC decreases and FEV also has a decrease, what does this mean
Restricted issue
