Exam 3 -- Vodcast Flashcards
What is the main function of the respiratory system?
supply body tissues with oxygen and dispose of carbon dioxide
What are the 4 process of the respiratory system?
- pulmonary ventilation
- external respiration
- transport of respiratory gases in the blood
- internal respiration
What is the process “pulmonary ventilation”?
breathing
What is the process “external respiration”?
movement of O2 from lungs to blood and CO2 from blood to lungs
What is the process “internal respiration”?
movement of O2 into tissue and CO2 from cells to blood
What are some structures of the airway?
nose
nasal cavity
pharynx
larynx
trachea
bronchi
lungs
alveoli
What are the 2 zones of the respiratory system?
respiratory zone
conducting zone
What is the respiratory zone?
where gas exchange happens
What is the conducting zone?
everything that doesn’t do gas exchange
What structures make up the respiratory zone?
alveoli
respiratory bronchioles
What structures make up the conducting zone?
trachea
bronchi
bronchioles
The trachea is made up of a lot of _________ to support the epithelial layer
cartilage
Are the airway walls well vascularized?
yes
What fibers/muscles make up the trachea/bronchi?
smooth muscle and elastic fibers
Does the airways have autonomic and/or local innervation?
yes
What are cilia?
fibers on epithelial cells for movement of mucus
What do goblet cells do?
secrete mucus
Why is fluid required for cilia function?
allows them to beat and move mucus up and out
What channel allows Cl-, Na+, and K+ into epithelial cells?
NKCC
What channel allows Cl- out of apical side of epithelial cells?
CFTR
How many Cl- are brought into an epithelial cells via NKCC?
2
How many Na+ are brought into an epithelial cells via NKCC?
1
How many K+ are brought into an epithelial cells via NKCC?
1
Where does the 2Cl- go after they enter the epithelial cell?
one leaves on the apical side and one stays inside the epithelial cell
Does Cl- build up or mainly leave epithelial cells?
build up
What is the result of Na+ and Cl- entering the apical side of epithelial cells?
water follows salt creating a saline layer in lumen for cilia
How does Na+ and H2O get to the lumen from the basilateral side of epithelial cells?
paracellular transport (in between cells)
What is the problem at the epithelial level in cystic fibrosis?
CFTR (Cl- channel) doesn’t work causing now salt for the water to follow resulting in no fluid layer for cilia to beat = thick viscous mucus
What is the problem at the epithelial level in ciliary dyskinesia?
Cilia have a defect causing them to now move well even though there is a saline layer present = increased infection risk
What is referred to as the “site of gas exchange”?
alveoli
Alveoli’s open ends are continuous with _______ of airways
lumen
The air facing surfaces of alveoli walls are lined with __________ alveolar cells
type I alveolar cells
How thick are the air facing surfaces of alveoli?
1 cell thick
What do type II alveolar cells do?
secrete surfactant
Why is the surface area of alveoli so large?
rapid gas exchange
In some alveolar walls, ______ permit the flow of air between alveoli?
pores
Why does the alveoli and bronchi have elastic fiber?
allows them to relax and contract
Why are alveoli so vascualrized?
gas exchange
Are type I or II alveolar cells made of gas exchange and why?
type I
one cell thick layer
How many total divisons are there in the airways?
24
What separates the 2 lungs?
mediastinum
How many lobes does the right lung have?
3
How many fissures does the right lung have?
2 (separates lobes 1and 2; lobes 2 and 3)
Which lung is shorter?
right lung
How many fissures does the left lung have?
1 (separates lobes 1and 2)
Which lung has a cardiac notch?
left
What is the membrane the surrounds the lung?
pleura membrane
What is the parietal pleura?
outer pleura membrane
What is the visceral pleura?
membrane directly on lung (inner membrane)
What is the slit-like space filled with pleural fluid called?
pleural cavity
What is the purpose of the pleura membranes?
keeps lungs adhered to chest wall
- pulling lungs out when inhaling
What are the muscles in the ribs that aid in respiration?
intercostal muscles
What do external intercostal muscles do?
enlarge the rib cage
* used in inspiration
What do the internal intercostal muscles do?
forced expiration
* moves ribs in
Innermost intercostal muscles help ___________ intercostal muscles function
internal costal
What is the phase for which way the external intercostal muscles run?
hands in pocket
What is the phase for which way the internal intercostal muscles run?
hands on chest
When you inhale…
rib cage moves IN/OUT
EXTERNAL/INTERNAL intercostal muscles are used
diaphragm CONTRACTS/RELAXES and moves UP/DOWN
rib cage moves OUT
EXTERNAL intercostal muscles are used
diaphragm CONTRACTS and moves DOWN
When you exhale…
rib cage moves IN/OUT
EXTERNAL/INTERNAL intercostal muscles are used
diaphragm CONTRACTS/RELAXES and moves UP/DOWN
rib cage moves IN
INTERNAL intercostal muscles are used
diaphragm RELAXES and moves UP
When you inspire the thoracic cavity increases or decreases?
increases
What is the most important muscle in respiration?
diaphragm
Does barometric pressure increase or decrease at high altitudes?
decreases
What is Dalton’s Law?
pressure of a mixture of gases is the sum of the pressures of the individual gases
What is the pressure of an individual gas in a mixture called?
partial pressure
How do you calculate partial pressure in dry air?
P = P atm x % of gas
How do you calculate partial pressure in humid air?
P = (P atm - H2O) x % of gas
What unit is airway pressure expressed in?
cm H2O
What are 3 examples of units of absolute presesuree?
PSI
atm
mmHg
What are 3 examples of units of relative pressure?
cm H2O
mmHg
Torr
What are individual gas partial pressures are measured in?
mmHg
What is tidal volume (VT)?
normal volume of air displaced in normal breathing at rest
What is expiratory reserve volume (ERV)?
amount of air that can be expired from lungs with effort after normal inspiration
What is inspiratory reserve volume (IRV)?
max amount of air that can be inhaled by force following a normal inspiration
What is residual volume (RV)?
volume of air remaining in the lungs after a max expiration
How do you find the inspiratory capacity?
inspiratory reserve volume + tidal volume
IRV + VT
How do you find vital capacity?
inspiratory reserve + expiratory reserve + tidal volume
IRV + ERV + VT
How do you find the functional residual capacity?
expiratory reserve volume + residual volume
ERV + RV
How do find lung capacity?
all of the volume added up
ERV + IRV + RV + VT
What is vital capacity?
total volume of air that can be expired after a max inspiration
What is the forced vital capacity (FEV)?
total volume of air that can be FORCIBLY expired after max inspiration
What is the FEV1?
volume of air that can be FORCIBLY expired in 1 second
What is the normal FEV1/FVC ratio?
0.8
(80% of air in lungs can be forced out in 1 sec)
What does the FEV1/FVC ratio represent?
% of air in lungs that can be forced out in 1 sec
Is asthma an obstructive or restrictive disease?
obstructive
In asthma, does FEV1/FVC ratio increase or decrease?
decrease
In asthma, does FEV1 or FVC decrease the most and why?
FEV1
harder to quickly force air out of narrow tube
In asthma, is it harder to breathe in or out?
out
In asthma is the FEV1/FVC ratio >, <, = 0.08?
< 0.80
Is fibrosis an obstructive or restrictive disease?
restrictive
In fibrosis, does FEV1/FVC ratio increase or decrease?
increases
Why is fibrosis a restrictive disease?
less of elasticity causing difficulty in expanding lungs
In fibrosis, does FEV1 or FVC decrease the most and why?
FVC
harder to expand lungs
In fibrosis, is it harder to breathe in or out?
in
In fibrosis is the FEV1/FVC ratio >, <, = 0.08?
> 0.80
What is dead space?
area in lungs/airway that does not participate in gas exchange
What are the 2 types of dead spaces?
anatomic dead space
functional dead space
What is anatomic dead space?
volume of conducting airways (everything but alveoli)
What is functional dead space?
alveolar that cannot gas exchange
What is physiological dead space?
total volume of dead spaces (anatomic + functional dead space)
What are the 2 types of ventilation?
pulmonary
alveolar
What is pulmonary ventilation?
volume of air moving in and out of the respiratory tract over a given time
How do you calculate minute ventilation (pulmonary ventilation)?
tidal volume x breaths/minute
What is alveolar ventilation?
volume of air moving in and out of alveoli over a given time
How do you calculate minute ventilation (alveolar ventilation)?
(tidal volume - dead space volume) x breaths/min
Why is there a large gradient for CO2 to diffuse from the blood to air?
there is essentially no CO2 in the air
Are arterial pressure for CO2 generally the same as alveolar pressure for CO2?
yes (maintains 40 mmHg)
Is it more advantageous to increase depth of breathing or lower rate of breathing to increase ventilation?
increase depth
What’s the difference between volumes and capacities?
capacity is the combination of 2 volumes
What supplies blood to the lungs?
pulmonary arteries
What’s the difference between pulmonary and systemic circulation?
pulmonary: moves blood between heart and lungs; re-oxygenates blood
systemic: moves blood between heart and rest of body; de-oxygenates blood
What is cellular v. pulmonary respiration?
cellular: oxygen is used to break down glucose to ATP
pulmonary: oxygen is taken into the lungs, and when you exhale, carbon dioxide and water vapor are released
What is the regular tidal volume?
500 mL
What is the partial pressure of H2O in humid air?
24 mmHg
Increased CO2 from exercise causes INCREASED/DECREASE alveolar ventilation?
increased
to replace CO2 with O2
What zone of alveoli are best ventilated?
zone 3 because alveoli aren’t too blown up making them more compliant and easier to ventilate
Is blown up alveoli more or less compliant?
less compliant
Is a deflated alveoli more or less compliant?
more compliant
How do you calculate alveolar pressure?
(2 x surface tension) / radius
What does the flat part on the surfactant curve represent?
the build up of surfactant before there is enough to open alveoli
