Respiratory System Flashcards
What are the four processes of respiration?
pulmonary ventilation, external respiration, transport of respiratory gases, internal respiration
What is pulmonary ventilation?
air moving in/out of lungs
What is external respiration?
pushing O2 into blood and CO2 out
What is gas transport?
moving CO2 and O2 throughout the blood
What is internal respiration?
movement of gases between blood and body cells
What structures are included in the upper respiratory system?
nose and pharynx
What does the nose do?
filters things out that shouldn’t go into your lungs and humidifies the air (adds moisture)
What does the pharynx do?
connects the nose/mouth to larynx
What structures are included in the lower respiratory system?
larynx, trachea, bronchi/bronchioles, diaphragm
What does the larynx do?
contains epiglottis and vocal cords
What is the purpose of the epiglottis?
helps to prevent aspiration
What does the trachea do?
lined with cilia to help move dust/debris out of lower respiratory system
What are the bronchi/bronchioles?
smalls tubes that carry air to lungs
What are the terminal bronchioles?
the last set of bronchioles
Why are bronchioles made of smooth muscle tissue?
so they can constrict/dilate
What type of muscle is the diaphragm and why?
skeletal muscle so you can voluntarily control it
What part of the bronchiole tree is the conducting zone?
the top… everything until the terminal bronchi (primary, secondary, etc)
What structures are included in the respiratory zone of the bronchiole tree?
terminal bronchi and alveoli
Where does external respiration occur?
respiratory zone
How many lobes does the right lung have?
3
How many lobes does the left lung have?
2
What is name of the connective tissue that surrounds each lung?
pleurae
Where is the apex + base of each lung?
apex = superior
base = inferior
Why are the pleura completely separate of each other?
if one lung collapses, the other won’t
What are the layers of the pleurae?
visceral, serous fluid, parietal
How does air enter the lungs?
pressure gradients… high –> low
What causes inspiration and expiration?
muscle movements that create pressure differentials
What happens to the the lung volume when you are breathing in?
diaphragm goes down to allow room for air
What is atmospheric pressure?
pressure of air outside the body
What is intrapulmonary pressure?
pressure of air in lungs
How do you calculate respiratory pressure?
resp pressure= intrapulmonary pressure- atmospheric pressure
When is the respiratory pressure a positive value?
exhaling… atm<intrapulmonary
When is the respiratory pressure a negative value?
inhaling… atm>intrapulmonary
How do the pressure gradients change?
contractions and relaxations
What happens when contractions increase the space in the thoracic cavity?
intrapulmonary pressure decreases and you inhale
What happens when contractions decrease the space in the thoracic cavity?
intrapulmonary pressure increases and you exhale
What is quiet breathing?
when you aren’t consciously aware that you’re breathing
Which three muscles are involved in quiet breathing?
diaphragm, external intercostals, internal intercostals
When does the diaphragm contract/relax during quiet breathing?
contract= inhale
relax= exhale
When do the external intercostals contract/relax during quiet breathing?
contract = inhale
relax = exhale
When do the internal intercostals contract/relax during quiet breathing?
contract = exhale
relax = inhale
Which muscles are involved in forced inspiration?
scalines and pectoral minor contract (also a stronger diaphragm contraction)
Which muscles are involved in forced expiration?
abdominal muscles and internal intercostals contract (all others relax)
What is inspiratory reserve?
amount of air you could breath in with maximal effort
What is expiratory reserve?
amount of air that could be exhaled with maximal effort
What is tidal volume?
amount of air you breath in/out at baseline
What is residual volume?
volume of air remaining in the lungs after forced expiration
What is vital capacity?
the total amount of air exhaled after maximal inhalation
What is minute ventilation and how is it calculated?
how much air is moving through the lungs in one minute
MV=breaths/min x volume/breath
What is forced vital capacity?
amount of air forcefully exhaled after a full inhale
What is forced expiratory volume?
amount of air exhaled during a set amount of time
What are restrictive lung disorders?
a decrease in lung volume caused by a decrease in compliance (stretchiness), costal ossification (stiffness), fibrosis (from smoking/dust), or weakening of inspirational muscles
What are obstructive lung disorders?
something obstructing the movement of air, usually the bronchioles are affected (bronchitis, asthma)
What is happening during an asthma attack and how does an inhaler help?
lumen of bronchioles is constricted, an inhaler helps the smooth muscle relax so the bronchioles will be their normal size
Why are the alveoli connected by pores?
allows air to circulate within them
Why are the alveoli surrounded by pulmonary capillaries?
brings the air (in alveoli) as close as possible to the blood (in capillaries)
Why is it important for there to be lymphatic capillaries around the lungs?
you don’t want fluid to build up here and they are able to fight infection
What are the three cell types of alveoli?
Type I, Type II, Alveolar Macrophages (resident)
Which cell type makes up a majority of alveolar cells?
Type I
Which does the alveolar cell type II cell do?
make/secrete surfactant and divide to make type I cells
Where are alveolar macrophages found?
Inside the alveolar cell membrane
Why is surfactant so important?
it keeps the alveoli from collapsing in on themselves, reduces surface tension of water droplets so they aren’t attracted to each other
What is the respiratory membrane?
interface between air and blood
What are the three main gases in the air you breathe?
O2, N2, CO2
What process happens at the respiratory membrane?
external respiration (O2 into blood and CO2 into air)
What is Dalton’s Law of Partial Pressure?
the partial pressure of gas is proportional to the percentage of gas in that mixture… partial pressures add up to total
What is Henry’s Law?
gas will dissolve into a liquid in proportion to its partial pressure… higher pressure difference=more/faster into solution
How quickly does blood get oxygenated?
less than a second
Why can hyperventilation be fatal?
causes too much CO2 to leave your blood (too much or too little is toxic)
What two ailments influence gas exchange?
pneumonia and emphysema
How does pneumonia affect gas exchange?
water builds up and the respiratory membrane has increased thickness
How does emphysema affect gas exchange?
there is less surface area in the alveoli which reduces the amount of places where gas exchange can occur
What is perfusion?
rate of blood flow in alveoli
What is ventilation?
how much air goes into the alveoli
What is the goal of ventilation-perfusion coupling?
obtaining optimal gas exchange
What is the smooth muscle in the capillaries for?
measures the pressure of O2 and constricts/dilates accordingly
When do bronchioles dilate?
when CO2 levels are elevated
When do pre capillary sphincters dilate?
when O2 levels are elevated
What effect does bronchiole dilation have?
causes an increase in air flow in/out of respiratory zone which leads to an increase of external respiration
What is the effect of dilation of pre capillary sphincters?
increasing blood flow to respiratory membrane which increases rate of external respiration
What does O2 found in blood attach to?
hemoglobin
What is an oxyhemoglobin?
heme bound to oxygen
What is a deoxyhemoglobin?
heme with no oxygen
What part of hemoglobin does CO2 bind to?
globin
How many oxygen molecules can one hemoglobin bind to?
4
What happens to the CO2 affinity of a hemoglobin when there is a lot of oxygen present? **
decreases
What happens to O2 affinity of a hemoglobin when more CO2 is present? **
increases
Describe the path of O2 from leaving the lungs to when it returns to the respiratory membrane.
leaving the lungs… 4 O2 on hemoglobin
at the tissues… a small percent of O2 leaves
respiratory membrane… O2 is ‘dropped off’ here
What are the three substances you can find CO2 in?
bound to globin, dissolved in plasma, bicarbonate ions (most common)
Why does your body convert CO2 to HCO3-?
because CO2 is toxic to the body in excess and it would cause your blood to become acidic… bicarbonate is a base
How is bicarbonate formed?
carbonic anhydrase combines CO2 with H2O (also results in productions of H+ ions)
What is the Bohr effect?
as pH changes so does O2 affinity for heme (pH more acidic = decreased affinity)
Are the shifts in pH significant when lots of CO2 is produced?
no its just a slight shift
Why does pH shift matter?
decreased pH causes O2 to have a lower affinity for hemoglobin and a higher affinity for CO2
