P3 chapter 23 THE RESPIRATORY SYSTEM Flashcards
Chemoreceptors in the brain are activated primarily by the presence in the cerebrospinal fluid of
a. hydrogen ions
b. oxygen ions
c. carbonic acid
d. bicarbonate ions
a. hydrogen ions
Carbon dioxide binds to the globin portion of hemoglobin to form
a. oxyhemoglobin
b. hemoglobin
c. carbonic anhydrase
d. carbaminohemoglobin
d. carbaminohemoglobin
Mucous membranes of the nasal passages, pharynx and trachea are lined with what type of epithelium?
a. stratified columnar
b. simple squamous
c. pseudostratified ciliated columnar
d. proprioceptors
c. pseudostratified ciliated columnar
The enzyme carbonic anhydrase causes
a. carbon dioxide to react with water
b. carbon dioxide to react with bicarbonate ions
c. hydrogen ions to react with bicarbonate ions
d. hydrogen ions to react with water
a. carbon dioxide to react with water
The term pulmonary ventilation refers to
a. external respiration
b. cellular respiration
c. internal respiration
d. breathing
d. breathing
If the air we breath contains 10 percent of Gas X, the partial pressure of Gas X is
a. 760 mm Hg
b. 76 mm Hg
c. 7.6 mm Hg
d. 0.76 mm Hg
b. 76 mm Hg
Nerves, pulmonary vessels, and bronchi enter the lungs at the
a. cupola
b. hilus
c. base
d. costal surface
b. hilus
As blood enters the systemic capillaries
a. PO2 is high in the blood and low in the tissues
b. PO2 is low in the blood and high in the tissues
c. PCO2 is high in the blood and low in the tissues
d. PCO2 is high in the blood and high in the tissues
b. PO2 is low in the blood and high in the tissues
The first respiratory branches after the trachea are called
a. lobar bronchi
b. segmental bronchi
c. primary bronchi
d. respiratory bronchi
c. primary bronchi
When oxygen combines with heme, what is formed?
a. oxyhemoglobin
b. hemoglobin
c. carbaminohemoglobin
d. carbonic acid
a. oxyhemoglobin
The right lung has
a. 2 fissures and 3 lobes
b. 1 fissure, 2 lobes, and the cardiac notch
c. 2 fissures, 3 lobes, and the cardiac notch
d. 1 fissure and 2 lobes
a. 2 fissures and 3 lobes
Tidal volume is
a. the amount of air that can be forced from the lungs after normal exhalation
b. the volume of air in one breath during normal relaxed breathing
c. about 5,800 mL
d. about 3,000 ml
b. the volume of air in one breath during normal relaxed breathing
During swallowing, the glottis is covered by
a. hyaline cartilage rings
b. the epiglottis
c. pseudostratified ciliated columnar epithelium
d. the tongue
b. the epiglottis
Some hydrogen ions in the blood are produced by the dissociation of
a. bicarbonate
b. carbonic acid
c. carbonic anhydrase
d. carbaminohemoglobin
b. carbonic acid
The amount of oxygen that can combine with heme is determined mainly by the
a. systolic blood pressure
b. partial pressure of oxygen
c. concentration of hydrogen ions
d. concentration of carbonic anhydrase
b. partial pressure of oxygen
During inspiration
a. alveolar pressure decreases
b. the thoracic cavity decreases in size
c. external intercostal muscles pull ribs down and in
d. posterior intercostal muscles contract
a. alveolar pressure decreases
Internal respiration occurs
a. between atmosphere and blood
b. between systemic capillaries and tissue cells
c. in bronchi and trachea
d. in the lungs
b. between systemic capillaries and tissue cells
The amount of oxygen released by the hemoglobin molecules in the blood to the tissues
a. decreases as PCO2 increases
b. increases as blood pH decreases (acidity increases)
c. decreases as temperature increases
d. increases as PCO2 decreases
b. increases as blood pH decreases (acidity increases)
Most carbon dioxide is carried in the blood
a. as part of a bicarbonate ion
b. as carbonic anhydrase
c. as dissolved carbon dioxide gas
d. bound to hemoglobin
a. as part of a bicarbonate ion
The respiratory membrane consists of a.
a single layer of epithelial cells
b. a single layer of epithelial cells and a basement membrane
c. two layers of epithelial cells and 2 basement membranes
d. two layers of epithelial cells
c. two layers of epithelial cells and 2 basement membranes
In the lungs
a. PCO2 is high in the alveoli and low in the capillaries
b. PO2 is low in the alveoli and high in the capillaries
c. PCO2 is low in the alveoli and high in the capillaries
d. PO2 is low in the alveoli and low in the capillaries
c. PCO2 is low in the alveoli and high in the capillaries
Surface tension of the alveolar fluid is reduced by the presence of
a. surfactant
b. serotonin
c. histamine
d. hyaline cartilage rings
a. surfactant
Exchange of respiratory gases occurs in all of the following except the
a. alveolar ducts
b. alveoli
c. respiratory bronchioles
d. terminal bronchioles
d. terminal bronchioles
The phrenic nerves innervate the
a. trachea
b. visceral pleura
c. alveoli
d. diaphragm
d. diaphragm




































