respiratory system part 3 Flashcards
TV
tidal volume
normal breathing at rest
IRV
inspiratory reserve volume
how much more you can breath in after normal inhale
ERV
expiratory reserve volume
how much more can breathe out after normal exhale
RV
residual volume
always some left
IC
inspiratory capacity
FRC
functional residual capacity
VC
vital capacity
TLC
total lung capacity
6000ML
IC formula
TV+ IRV
FRC formula
ERV + RV
VC formula
TV+IRV+ERV
TLC formula
TV+IRV+ERV+RV
dead space
inspired air that never contributes to gas exchange
Anatomical dead space
volume of the conducting zone conduits (~150 ml
Alveolar dead space
alveoli that cease to act in gas exchange due to collapse or obstruction
Spirometer
instrument used to measure respiratory volumes and capacities
Obstructive pulmonary disease
increased airway resistance (e.g., bronchitis)
harder to get air out
inflammation, mucus COPD emphysema
Restrictive disorders
reduction in total lung capacity due to structural or functional lung changes (e.g., fibrosis or TB)
difficulty getting air in, expanding lungs. lung tissue not as complient
Minute ventilation
total amount of gas flow into or out of the respiratory tract in one minute
Forced vital capacity (FVC):
gas forcibly expelled after taking a deep breath
Forced expiratory volume (FEV):
the amount of gas expelled during specific time intervals of the FVC
what increases as a result of obstructive disease
Increases in TLC, FRC, and RV may occur as a result of obstructive disease
what reduces as a result of restrictive disease
Reduction in VC, TLC, FRC, and RV result from restrictive disease
what happens to alveoli in obstructive disorder
keep expanding until burst
Dalton’s Law
Total pressure exerted by a mixture of gases is the sum of the pressures exerted by each gas
The partial pressure of each gas is directly proportional to its percentage in the mixture
percentage of nitrogen in atmopshere with partial pressure
78.6%
597 mm Hg
percentage of oxygen in atmopshere with partial pressure
20.9%
159 mmHg
Henry’s Law
prescence of gas in liquid is proportional to its partial pressure
at equilibrium the partial pressures will be even
amount of gas dissolved also depends on solubility
solubility of CO2
CO2 is 20 times more soluble in
water than O2
solubility of nitrogen
very little nitrogen dissolves in water at surface pressure, which is why more O2 in us even though nitrogen has higher partial pressure
the bends
dive deep nitrogen absorbed due to increase in pressure, come up too fast and nitrogen rapidly escapes as bubbles
hyperbonic chamberq
high pressure chamber, slowly changes pressure
Alveoli contain more CO2 and water vapor than atmospheric air, due to
Gas exchanges in the lungs
Humidification of air in nasal cavity
why 1% o2 drop in trachea
due to diffusion in trachea tissue
why 7% o2 drop when reach alveoli
because diffuses into blood stream
External Respiration
Exchange of O2 and CO2 across the respiratory membrane
external respiration influenced by
Partial pressure gradients and gas solubilities
Ventilation-perfusion coupling
Structural characteristics of the respiratory membrane
how do you get a faster diffusion rate
bigger pressure difference, higher solubility
CO2 concentration in deoxygenated blood vs CO2 concentration in alveolus
46mmhg in bloo, 40mmhg in alveolus so diffuse into alveolus
O2 concentration in deoxygenated blood vs O2 concentration in alveolus
100mmhg in aleolus and 40 mmhg in blood so diffuse rapidly into blood
O2 concentration in oxygenated blood vs O2 concentration in cell
100mmhg in blood and 5mmhg in cell so diffuse into cell and then into mito
CO2 concentration in oxygenated blood vs CO2 concentration in cell
40mmhg in blood and more than 40mmhg in cell so diffuse into blood`
Venous blood Po2 =
40 mm Hg
Alveolar Po2 =
= 104 mm Hg
O2 partial pressures reach equilibrium of — in how much time
of 104 mm Hg in ~0.25 seconds, (due to big difference between pressures) about 1/3 the time a red blood cell is in a pulmonary capillary
Venous blood Pco2 =-
45 mm Hg
Alveolar Pco2 =
40 mm Hg
given the partial pressure differences in blood and alveoli of o2 and co2, how does CO2 diffuses in equal amounts with oxygen
CO2 is 20 times more soluble in plasma than oxygen
Ventilation
flow of gas reaching the alveoli (AVR
Perfusion
blood flow reaching the alveoli
Ventilation-Perfusion Coupling
Ventilation and perfusion must be matched (coupled) for efficient gas exchange
Ventilation-Perfusion Coupling Changes that occur to match physiological needs
Where alveolar CO2 is high, bronchioles dilate (increase ventilation)
Where alveolar CO2 is low, bronchioles constrict (decrease ventilation)
Internal Respiration partial pressures vs external respiration partial pressures
Partial pressures and diffusion gradients are reversed compared to external respiration
Po2 in tissue is always lower than in systemic arterial blood
Pco2 is 5 mm Hg higher in tissues
O2% dissolved in plasma
1.5%
O2% on hemoglobin
98.5% loosely bound to each Fe of hemoglobin (Hb) in RBCs
CO2% in plasma
7 to 10% dissolved in plasma
CO2% in hemoglobin
20% bound to globin of hemoglobin (carbaminohemoglobin
CO2% in bicarbonate
70% transported as bicarbonate ions (HCO3–) in plasma
Rate of loading and unloading of O2 in hemoglobin is regulated by
PO2
temperature
Ph
PCO2
which three of the factors affecting rate of unloading o2 influence 3D shape of hemoglobin
Temperature
Blood pH
Pco2
how much O2 is unloaded during one systemic circulation
20–25% of bound O2
If O2 levels in tissues drop
More oxygen dissociates from hemoglobin and is used by cells
Respiratory rate or cardiac output need not increase instantly
Haldane Effect
The amount of CO2 transported is affected by the Po2
The less O2 hemoglobin saturation, the more CO2 can be carried in the blood (because co2 with water makes acid)
how can Changes in respiratory rate alter blood pH
slow shallow breathing allows CO2 to accumulate in the blood, causing pH to drop
Changes in ventilation can be used to adjust pH when it is disturbed by metabolic factors
brain parts that control respiration
neurons in the medulla and pons
Genesis of respiratory system
Ventral respiration group controls normal breathing (eupnea)
Dorsal respiration group responds to changes in stretch of lungs and Po2 in blood
Signal sent down the phrenic (diaphragm) and intercostal nerves
How does Co2 affect breathing rate
Increase CO2 in blood changes PH, and the medulla in brain signals increase breathing rate
Hyperventilation
Increased rate of breathing that exceeds body’s need to remove CO2, too much CO2 released
Hypercapnia
Increased Co2 levels
Decrease in CO2 causes
Blood vessels to restrict
Hypocapnia
Low levels of CO2
Apnea
Where breathing stops that can happen when PCO2 is too low
Three neural factors that cause increase in ventilation as exercise begins
Psychological stimuli (anticipation of exercise)
Simultaneous cortical motor activation of skeletal muscles and respiratory centers
Excitatory impulses reaching respiratory centers
Fast travel to altitudes above 8000 feet may produce symptoms of
Acute mountain sickness (AMS)
Headaches, shortness of breath, nausea, dizziness
Acclimation
Respiratory and hematopoietic adjustments to altitude
Minute ventilation increases and stabilized in a few days to 2-3L/min higher than at sea level
EPO production
Decline of O2 in blood stimulates the kidneys to accelerate production of EPO
Chronic obstructive pulmonary disorder
Chronic bronchitis and emphysema
Irreversible
Dyspnea
Eupnea
Normal breathing
Apnea
Stopping in breathing some point in time
No rhythm
Dyspnea
Difficult or labored breathing
Asthma
Coughing, dyspnea, wheezing, and chest tightness
Active inflammation with bronchospasms
Tuberculosis
Infectious disease caused by bacterium
Fever, night sweats, weight loss, cough, and spitting up blood
12 month course of antibiotics
Lung cancer
Leading cause of cancer deaths in North America
90% of all cases are result of smoking
How to inflate balloon with muscles and mechanics
Increase volume in lungs by diaphragm pushing down, causing decrease in pressure and we inhale
Air forced out by abdominal muscles pushing diaphragm up further using internal costars
