THE RESPIRATORY SYSTEM PT.2
which describes the respiratory cycle
1 complete inspiration and expiration
what is the normal systemic aterial blood value for PCO2
40 mm Hg
hypoxic drive refers to a condition where the respiratory centers of the brainstem responds to which of the following
Po2 of arterial blood
__________ is a general term for a drop in the pH of blood below 7.35
acidosis
what is the role of the pontine (pneumotaxic) respiratory group?
adjust respiratory rate based on stimuli from limbic system or cerebral cortex
what is the role of the dorsal respiratory group
adjust respiratory rate based on stimuli from peripheral chemoreceptors
______ refers to a shift in the pH of blood above 7.45
alkalosis
which term refers to the conducting zones of the respiratory system because they are incapable of gas exchange
anatomical dead space
Where does systemic gas exchange occur?
at the capillary networks of the tissues
why does air flow into the lungs during respiration
atmospheric pressure is greater than intrapulmonary pressure, and air flows towards the lower pressure area
Most of the carbon dioxide in the blood is transported in the form of ____________ dissolved in the plasma
bicarbonate
carbon dioxide is transported in different forms in the blood. what is the most common form?
bicarbonate ion
airway resistance in the lungs is usually controlled by changing the diameter of which of the following
bronchioles
Chronic ____ is characterized by a reduction in the number of cilia lining the airway and increased mucus production.
bronchitis
which is true about carbon dioxide loading
carbonic anydrase catalyzes the conversion of C02 and H20 into bicarbonate and hydrogen ions
which factor is typically responsible for setting the respiratory rate in healthy individuals
cerebrospinal fluid pH
irritants in the lower respiratory system may stimulate which of the following
coughing
which is a degenerative lung disease characterized by a breakdown of alveoli and diminishing surface area available for gas exchange
emphysema
select two examples of chronic obstructive pulmonary disease from the list below
emphysema, chronic bronchitis
which term refers to relaxed, quiet breathing
eupnea
when the diaphragm relaxes, air is forced from the lungs. this process is known as ___________
expiration
which muscles are used for inspiration
external intercostals, sternocleiodomastoid, scalenes
T/F: all of the oxygen transported in the blood is usually unloaded at a systemic capillary
false
T/F: the residual volume may be exhaled with a forceful expiration
false
T/F: the respiratory control centers of the brainstem are involved in voluntary respiration
false
a person expelling air while yelling is performing which type or breathing
forced
which term refers to the volume of air (or percentage of the vital capacity) that can be exhaled in a specific amount of time.
forced expiratory volume (FEV)
deoxygenated blood can carry more carbon dioxide, whereas oxygenated blood has a lower carbon dioxide carrying capacity. this phenomenon is known as the _______ effect
haldane
the term _____ describes a condition where there is an excess of CO2 in aterial blood (PCO2 greater than 43 mm Hg)
hypercapnia
the normal PCO2 of arterial blood is between 37 and 43 mm Hg. which term refers to a Pco2 of less than 37 mm Hg
hypocapnia
insufficient oxygen levels in a tissue is called ______
hypoxia
during the respiratory cycle, the intake of air is called
inspiration
in a healthy individual, which of these volumes would have the greatest numberical value
inspiratory reserve volume
which two muscles or muscle groups are primarily responsible for resting (non-forced) inspiration?
intercostals, diaphragm
As the thoracic cavity expands, the visceral pleura clings to the parietal pleura, and the surface of the lung is pulled outward. why does this increase in lung volume cause inspiration.
intrapulmonary pressure is temporarily lower than atmospheric pressure
exposure to smog and dust can lead to coughing and bronchoconstriction, which type of respiratory receptors initiate this response
irritant response
which best describes the action of carbonic anhydrase
it converts carbon dioxide and water to carbonic acid which dissociates into bicarbonate and hydrogen ions
which two factors contribute most to airflow resistance
lung compliance, diameter of the bronchioles
which two factors contribute most to airflow resistance?
lung compliance, diameter of the bronchioles
which of these occurs during exhalation
lung volume decrease, intrapulmonary pressure increases
central chemoreceptors in the brain stem that are involved in respiratory control respond most directly to changes in which of the following
pH
Chemoreceptors in the carotid and aortic bodies are called_______ chemoreceptors
peripheral
which is often increased in individuals with pulmonary disease
physiological dead space
which locations contain the brainstem respiratory centers
pons, medulla oblongata
An inactive person, unconscious of their respiratory rate, is performing __ breathing
quiet
how is the functional residual capacity calculated
residual volume + expiratory reserve volume (RV + ERV)
what is the correct formula for calculating total lung capacity
residual volume+ vital capacity
which decreases surface tension in the fluids of the alveoli
surfactant
the lungs of premature infants often develop respiratory distress syndrome. why do these infants experience alveolar sac collapse
surfactant is not produced yet in adequate quantities.
which best describes the expiratory reserve volume (ERV)
the amount of air that may be exhaled over the tidal volume
which best describes what happens during exhalation
the diaphragm relaxes, intrapulmonary pressure increases, air flows out
oxygen loading in the lungs decreases hemoglobin's affinity for H+ . how does this promte alveolar gas exchange
the release H+ combines with HCO3- to form free CO2, which can diffuse out of the blood
which term refers to the amount of air inhaled and exhaled during one cycle of quiet breathing
tidal volume
what is the correct calculation for vital capacity
tidal volume plus expiratory reserve volume plus inspiratory reserve volume
T/F: prolonged exposure to oxygen at 2.5 ATM can be toxic
true
T/F: the chloride shift allows RBC's to continue to produce carbonic acid
true
pulmonary compliance is reduced in which of the following
tuberculosis patients
The sum of the expiratory reserve volume, tidal volume, and inspiratory reserve volume is the __ capacity
vital
