Week 5 Respiratory system Flashcards
Type I PNEUMOCYTES
Epithelium is Simple squamous , Function is to do Gas Exchange
Type II PNEUMOCYTES
Produces Surfactant
Surfactant is produced and released at what age?
Produced at 24 weeks gestation, released at birth
What is surfactant?
A lipid and protein mixture that lines the alveolis
What is the function of surfactant?
decreased surface tension during exhale, so lungs dont collapse
What chemical causes surfactant to be released at birth?
cortisol
Internal respiration is :
respiration between cell capillary and alveoli
External respiration is:
The respiration occurring between the atmosphere and lungs
What is another name for external respiration?
ventilation
Air always flows from ____ to _____.
high to low
Barometer detects _______ exerted by the ________.
pressure, atmosphere
Boyle’s law states that pressure and volume are ______ ______.
inversely proportional
Intrapulmonary pressure is
Pressure inside the lungs
Intrapulmonary volume is
volume inside the lungs
The atmospheric pressure at sea level is
760 mmHg
At rest, _________ pressure and __________ pressure are the same.
atmospheric and intrapulmonary (760 mmHg)
At rest ____ levels are ___ in blood and ____ levels are ____ in blood.
At rest O2 levels are low in blood and CO2 levels are high in blood.
Lung volume at rest is around ____ ml of air
40 ml
How do we make air enter the lungs if the two pressures are the same?
By changing the pressure inside the lungs, since you can’t change the pressure of the atmosphere
Steps of inspiration:
low O2/High CO2 -> stimulates chemoreceptors -> stimulates medulla (respiratory center) -> stimulates phrenic nerve -> stimulates diaphragm/respiratory muscles -> diaphragm/muscles move down & out -> negative pressure is then created in lungs -> thoracic veins drain into lungs -> increase in intrapulmonary volume-> decrease in intrapulmonary pressure (4hgmm) -> air enters lungs
what are chemoreceptors?
receptors that respond to chemicals
What stimulates the medulla?
increase in CO2 and decrease in O2
What are the two types of chemoreceptors ?
Type 1: central receptors and Type 2: peripheral receptors
Central receptors are located near the ______.
medulla
Central receptors detect ____ concentration in ___. By detecting ____ concentration it can tell if ___ has increased.
Central receptors detect “H” concentration in CSF. By detecting “H” concentration it can tell if CO2 has increased.
Increase in “H” concentration means a decrease in __ and increase in ___ levels.
pH, CO2
The central receptor is the _____ chemoreceptor for the respiratory system. It can override what the ________ chemoreceptors are telling the medulla.
main, peripheral
Peripheral receptors are located in the ______ ______ & _______ _________.
carotid artery & aortic bodies
Peripheral receptors detect a decrease in __ levels and if decreased it stimulates the ________.
O2, medulla
The higher brain centers , ______ ______, can override both the chemoreceptors and tell the ______ ______ what it wants it to do.
cerebral cortex, respiratory center
For expiration to occur, the __________ ________ must be less than the ___________ _________.
atmospheric pressure, intrapulmonary pressure.
Expiration steps:
Inhalation caused lungs to fill with air -> this stimulates stretch receptors w/in medulla -> this inhibits the phrenic nerve -> This inhibits diaphragm and respiratory muscles -> diaphragm and muscles relax -> diaphragm moves up and muscles move inward -> lungs fall back on themselves (recoiling property) -> blood is pushed out of the lungs -> this decreases intrapulmonary volume-> in turn increasing intrapulmonary pressure (8hgmm)-> then air leaves lungs
TV
tidal volume
IRV
Inspiratory reserve volume
IC
Inspiratory Capacity
VC
Vital capacity
TLC
Total lung capacity
ERV
expiratory reserve volume
RV
residual volume
FRC
functional residual capacity
EC
expiratory capacity
Tidal volume is
A normal breath (1 inhale & 1 exhale)
Inspiratory reserve volume is
Amount of air you can forcefully inhale after a normal inhale
Expiratory reserve volume is
Amount of air you can forcefully exhale after a normal exhale
inspiratory capacity is
Amount of air your lungs can inhale
Tidal Volume + Inspiratory Reserve Volume =
Inspiratory Capacity
Expiratory capacity is :
Total amount of air the lungs are able to exhale.
Tidal volume + Expiratory reserve volume =
Expiratory capacity
Residual volume is :
Amount of air always left in the lungs
Functional residual capacity is:
Amount of air left in the lungs after a normal exhale
Expiratory reserve volume + residual volume =
functional residual capacity
Vital capacity is
Amount of air that can be manipul- ated
IRV + TV + TLC =
vital capacity
Total lung capacity is
Total amount of air your lungs can hold
__% of oxygen that enters our blood stream diffuses into the plasma.
2%
__% of oxygen that enters our blood enters the red blood cells, binds with ___, and forms _____________.
98%, hgb, oxy-hemoglobin
Steps to CO2 transport in venous blood
CO2 enters capillary -> CO2 and H20 combine via CARBONIC ANHYDRASE (ENZYME) -> you then get H2CO3 (carbonic acid)-> carbonic acid then breaks down into Hydrogen and bicarbonate (H + HCO3-) -> bicarbonate (HCO3-) then leaves the RBC and Chloride comes in via alkaline tide pump
__ % of CO2 diffuses into the capillaries.
70
What is the alkaline tide pump ?
a pump that allows Bicarbonate (HCO3-) and Chloride (Cl) to enter and exit the RBC in opposite directions
__% CO2 is bound to hgb.
20
When CO2 is bound to HgB it is called
carboaminohemoglobin
The rest of the __% of CO2 dissolves in plasma.
10
Steps to CO2 release from venous blood
Bicarbonate comes back in and Chloride exits the RBC via alkaline tide pump-> once bicarbonate is back in it combines with the Hydrogen it once left and forms bicarbonate-> bicarbonate then breaks down into CO2 and H20 via carbonic anhydrase(enzyme)->then the co2 diffuses out and enters alveoli
What happens to carboaminohemoglobin in co2 RELEASE?
it breaks up into CO2 and Hgb
Metabolic acidosis is due to
Excess acid in body or Not enough base in body
Respiratory acidosis is due to
excess CO2 in body
Metabolic alkalosis is due to
Excess base in body or Not enough acid in body
Respiratory alkalosis is due to
not enough CO2 in the body
What system compensates for metabolic acidosis ?
Respiratory system
How do you compensate for metabolic acidosis
hyperventilation - releasing CO2
What organ compensates for Respiratory acidosis ?
kidneys
How do you compensate for Respiratory acidosis
kidneys reabsorb bicarbonate (HCO3-)
What system compensates for metabolic alkalosis ?
respiratory system
How do you compensate for metabolic alkalosis?
Hypoventilation – retaining CO2
What organ compensates for Respiratory alkalosis ?
kidneys
How do you compensate for respiratory alkalosis?
Kidneys will increase secretion of HCO3-
