Ch. 22 Respiratory System Flashcards
Which of the following anatomical structures is not part of the conducting zone?
A. Pharynx.
B. Nasal cavity.
C. Alveoli.
D. Bronchi.
C. Alveoli.
The alveoli are part of the respiratory zone, where gas exchange occurs. The conducting zone only includes structures that move air, not where exchange takes place.
Incorrect Answers:
A. Pharynx: Part of the conducting zone, helping to move air between the nasal cavity and larynx.
B. Nasal cavity: Filters, warms, and humidifies air—functions of the conducting zone.
D. Bronchi: Branching airways that conduct air deeper into the lungs, part of the conducting zone.
What is the function of the conchae in the nasal cavity?
A. Increase surface area.
B. Exchange gases.
C. Maintain surface tension.
D. Maintain air pressure.
A. Increase surface area.
The conchae increase surface area in the nasal cavity, enhancing warming, humidifying, and filtering of the air.
Incorrect Answers:
B. Exchange gases: Gas exchange occurs in alveoli, not the nasal cavity.
C. Maintain surface tension: This is a function of surfactant in alveoli.
D. Maintain air pressure: The nasal cavity does not regulate air pressure.
The fauces connects which of the following structures to the oropharynx?
A. Nasopharynx.
B. Laryngopharynx.
C. Nasal cavity.
D. Oral cavity.
D. Oral cavity.
The fauces is the archway at the back of the oral cavity that opens into the oropharynx.
Incorrect Answers:
A. Nasopharynx: Connects to the nasal cavity, not the oral cavity.
B. Laryngopharynx: Connects to the esophagus and larynx, located inferior to the oropharynx.
C. Nasal cavity: Connects to the nasopharynx, not the oropharynx.
Which of the following are structural features of the trachea?
A. C-shaped cartilage.
B. Smooth muscle fibers.
C. Cilia.
D. All of the above.
D. All of the above.
The trachea contains C-shaped cartilage rings for structure, smooth muscle (especially at the open part of the rings), and cilia to help move mucus and debris upward toward the throat.
Incorrect Answers:
A–C individually: Each one is a correct feature, but ‘All of the above’ is the most complete answer.
Which of the following structures is not part of the bronchial tree?
A. Alveoli.
B. Bronchi.
C. Terminal bronchioles.
D. Respiratory bronchioles.
A. Alveoli.
The alveoli are part of the respiratory zone, not the bronchial tree. The bronchial tree ends at the terminal bronchioles.
Incorrect Answers:
B. Bronchi: Part of the bronchial tree; they branch into smaller airways.
C. Terminal bronchioles: The final part of the conducting portion of the bronchial tree.
D. Respiratory bronchioles: The transitional area where gas exchange begins, just past the end of the bronchial tree.
What is the role of alveolar macrophages?
A. To secrete pulmonary surfactant.
B. To secrete antimicrobial proteins.
C. To remove pathogens and debris.
D. To facilitate gas exchange.
C. To remove pathogens and debris.
Alveolar macrophages are immune cells that patrol the alveoli and phagocytose foreign particles and microorganisms.
Incorrect Answers:
A. To secrete pulmonary surfactant: This is done by Type II alveolar cells.
B. To secrete antimicrobial proteins: Not their primary role—though they may contribute, it’s not their defining function.
D. To facilitate gas exchange: This is the role of Type I alveolar cells and capillary endothelium.
Which of the following structures separates the lung into lobes?
A. Mediastinum.
B. Fissure.
C. Root.
D. Pleura.
B. Fissure.
A fissure is a deep groove that divides the lungs into lobes—the right lung has an oblique and horizontal fissure, and the left lung has just an oblique fissure.
Incorrect Answers:
A. Mediastinum: The central space in the thoracic cavity between the lungs.
C. Root: Where vessels, bronchi, and nerves enter the lung—not involved in lobar division.
D. Pleura: A serous membrane that covers the lungs, but doesn’t separate lobes.
The (BLANK) system consists of organs and structures that allow us to breathe by taking in oxygen and expelling carbon dioxide.
A. Interlobular.
B. Respiratory.
C. Pulmonary.
D. Bronchial.
B. Respiratory.
The respiratory system is the collective term for all the organs and structures involved in breathing, including the nose, pharynx, larynx, trachea, bronchi, and lungs. Its main function is gas exchange—bringing in oxygen and removing carbon dioxide.
Incorrect Answers:
A. Interlobular: Refers to small structures between lobules, not a system.
C. Pulmonary: Describes things related to the lungs, but not the full system.
D. Bronchial: Refers specifically to the bronchi or bronchial tree, not the entire system.
The (BLANK) is a tube connected to the trachea that branches into many subsidiaries and provides a passageway for air to enter and leave the lungs.
A. Trachea.
B. Illiac.
C. Aorta.
D. Bronchus.
D. Bronchus.
A bronchus is one of the two main branches off the trachea, each leading to a lung. It then further divides into smaller airways, allowing air to pass into and out of the lungs.
Incorrect Answers:
A. Trachea: The trachea is the main airway before it splits into bronchi.
B. Illiac: Refers to a region or artery near the pelvis—unrelated to the respiratory system.
C. Aorta: The major artery carrying blood from the heart—not part of the airway system.
A section of the lung that receives its own tertiary bronchus is called the (BLANK).
A. Bronchopulmonary segment.
B. Pulmonary lobule.
C. Interpulmonary segment.
D. Respiratory segment.
A. Bronchopulmonary segment.
Each bronchopulmonary segment is a distinct region of a lung served by a tertiary bronchus, making it a functionally and anatomically separate unit.
Incorrect Answers:
B. Pulmonary lobule: A smaller subdivision within a bronchopulmonary segment.
C. Interpulmonary segment: Not a recognized anatomical term.
D. Respiratory segment: A nonstandard term; could be confused with respiratory zone, but not accurate here.
The (BLANK) circulation picks up oxygen for cellular use and drops off carbon dioxide for removal from the body.
A. Pulmonary.
B. Interlobular.
C. Respiratory.
D. Bronchial.
A. Pulmonary.
The pulmonary circulation carries deoxygenated blood from the heart to the lungs and returns oxygenated blood back to the heart for systemic distribution.
Incorrect Answers:
B. Interlobular: Not a circulation type—refers to small anatomical structures between lobules.
C. Respiratory: Not a distinct circulatory pathway.
D. Bronchial: Supplies lung tissue itself with oxygen but is not the primary route for systemic gas exchange.
The pleura that surrounds the lungs consists of two layers, the (BLANK).
A. Visceral and parietal pleurae.
B. Mediastinum and parietal pleurae.
C. Visceral and mediastinum pleurae.
D. None of the above.
A. Visceral and parietal pleurae.
The visceral pleura covers the lungs’ surface, and the parietal pleura lines the thoracic cavity.
Incorrect Answers:
B & C: The mediastinum is a region, not a pleural membrane.
D. None of the above: Incorrect because option A is accurate.
The (BLANK) is a(n) opening that allows airflow between neighboring alveoli:
A. Alveolar pore.
B. Alveolar sac.
C. Alveolar macrophage.
D. Alveolar duct.
A. Alveolar pore.
Alveolar pores (also known as pores of Kohn) are small openings between adjacent alveoli that allow air to circulate between them, helping to equalize pressure and provide alternate pathways for airflow if certain passages are blocked.
Incorrect Answers:
B. Alveolar sac: A cluster of alveoli at the end of an alveolar duct; not an opening itself.
C. Alveolar macrophage: An immune cell that removes debris—not a structure involved in airflow.
D. Alveolar duct: A small airway that leads into alveolar sacs, not between alveoli themselves.
Which of the following processes does atmospheric pressure play a role in?
A. Pulmonary ventilation.
B. Production of pulmonary surfactant.
C. Resistance.
D. Surface tension.
A. Pulmonary ventilation.
Atmospheric pressure is critical in pulmonary ventilation—it drives air into and out of the lungs due to pressure gradients.
Incorrect Answers:
B. Pulmonary surfactant: Produced by Type II alveolar cells, not influenced by external pressure.
C. Resistance: Affected by airway diameter, not directly by atmospheric pressure.
D. Surface tension: Caused by alveolar fluid, not atmospheric pressure.
A decrease in volume leads to a(n) (BLANK) pressure.
A. Decrease in.
B. Equalization of.
C. Increase in.
D. Zero.
C. Increase in.
According to Boyle’s Law, pressure and volume are inversely related—a decrease in volume increases pressure.
Incorrect Answers:
A. Decrease in: Opposite of Boyle’s Law.
B. Equalization of: Describes what happens between compartments, not within a space.
D. Zero: Would only occur in a vacuum, not physiologically applicable here.
The pressure difference between the intra-alveolar and intrapleural pressures is called (BLANK).
A. Atmospheric pressure.
B. Pulmonary pressure.
C. Negative pressure.
D. Transpulmonary pressure.
D. Transpulmonary pressure.
Transpulmonary pressure = intra-alveolar pressure – intrapleural pressure. It keeps the lungs expanded.
Incorrect Answers:
A. Atmospheric pressure: Refers to external air pressure, not lung mechanics.
B. Pulmonary pressure: Too vague; not a defined pressure term.
C. Negative pressure: Describes a condition, not a specific differential pressure.
Gas flow decreases as (BLANK) increases.
A. Resistance.
B. Pressure.
C. Airway diameter.
D. Friction.
A. Resistance.
Higher resistance (e.g., from narrowed airways) makes it harder for air to flow.
Incorrect Answers:
B. Pressure: Higher pressure generally increases gas flow.
C. Airway diameter: Increasing diameter reduces resistance and improves flow.
D. Friction: Technically part of resistance, but not the most specific answer here.
Contraction of the external intercostal muscles causes which of the following to occur?
A. The diaphragm moves downward.
B. The rib cage is compressed.
C. The thoracic cavity volume decreases.
D. The ribs and sternum move upward.
D. The ribs and sternum move upward.
External intercostal contraction elevates the ribs and sternum, increasing thoracic volume.
Incorrect Answers:
A. Diaphragm moves downward: True, but due to diaphragm contraction, not intercostals.
B. Rib cage is compressed: Opposite effect; that happens with internal intercostals.
C. Thoracic volume decreases: False—volume increases during inspiration.
Which of the following prevents the alveoli from collapsing?
A. Residual volume.
B. Tidal volume.
C. Expiratory reserve volume.
D. Inspiratory reserve volume.
A. Residual volume.
Residual volume is the air that remains in the lungs after maximum exhalation, preventing alveolar collapse.
Incorrect Answers:
B. Tidal volume: Normal breath volume; not the primary factor preventing collapse.
C. Expiratory reserve volume: Air exhaled beyond tidal volume, but doesn’t prevent collapse.
D. Inspiratory reserve volume: Related to deep inhalation, not alveolar stability.
Gas moves from an area of (BLANK) partial pressure to an area of (BLANK) partial pressure.
A. Low; high.
B. Low; low.
C. High; high.
D. High; low.
D. High; low.
Gases diffuse down their partial pressure gradients—from high to low pressure, like oxygen from alveoli to blood.
Incorrect Answers:
A. Low; high: Opposite of how diffusion works.
B. Low; low: No gradient, so no net movement.
C. High; high: No pressure difference to drive movement.
When ventilation is not sufficient, which of the following occurs?
A. The capillary constricts.
B. The capillary dilates.
C. The partial pressure of oxygen in the affected alveolus increases.
D. The bronchioles dilate.
A. The capillary constricts.
Poor ventilation leads to low oxygen levels in alveoli, which causes local vasoconstriction of the capillaries to redirect blood to better-ventilated areas.
Incorrect Answers:
B. Capillary dilates: That would increase perfusion to a poorly ventilated area—inefficient for gas exchange.
C. PO₂ increases: Ventilation is insufficient, so PO₂ drops.
D. Bronchioles dilate: Bronchioles may dilate in response to CO₂, not low ventilation alone.
Gas exchange that occurs at the level of the tissues is called (BLANK).
A. External respiration.
B. Interpulmonary respiration.
C. Internal respiration.
D. Pulmonary ventilation.
C. Internal respiration.
Internal respiration is the exchange of gases between blood and tissues.
Incorrect Answers:
A. External respiration: Occurs between alveoli and blood.
B. Interpulmonary respiration: Not a recognized term.
D. Pulmonary ventilation: Refers to breathing (air movement), not gas exchange.
The partial pressure of carbon dioxide is 45 mm Hg in the blood and 40 mm Hg in the alveoli. What happens to the carbon dioxide?
A. It diffuses into the blood.
B. It diffuses into the alveoli.
C. The gradient is too small for carbon dioxide to diffuse.
D. It decomposes into carbon and oxygen.
B. It diffuses into the alveoli.
CO₂ moves from high (blood, 45 mm Hg) to low (alveoli, 40 mm Hg) pressure—into the alveoli for exhalation.
Incorrect Answers:
A. Into the blood: Would occur if alveolar CO₂ were higher.
C. Gradient too small: Even small gradients drive diffusion.
D. Decomposes: CO₂ is stable—it diffuses, not decomposes.
Oxyhemoglobin forms by a chemical reaction between which of the following?
A. Hemoglobin and carbon dioxide.
B. Carbonic anhydrase and carbon dioxide.
C. Hemoglobin and oxygen.
D. Carbonic anhydrase and oxygen.
C. Hemoglobin and oxygen.
Oxyhemoglobin is formed when oxygen binds to hemoglobin.
Incorrect Answers:
A. Hemoglobin + CO₂: Forms carbaminohemoglobin, not oxyhemoglobin.
B. Carbonic anhydrase + CO₂: Involved in converting CO₂ into bicarbonate.
D. Carbonic anhydrase + O₂: Unrelated pairing.
Which of the following factors play a role in the oxygen–hemoglobin saturation / dissociation curve?
A. Temperature.
B. pH.
C. BPG.
D. All of the above.
D. All of the above.
Temperature, pH, and BPG all affect hemoglobin’s affinity for oxygen, shifting the curve right or left.
Incorrect Answers:
A. Temperature: Increased temp reduces affinity (right shift).
B. pH: Lower pH reduces affinity (Bohr effect).
C. BPG: Binds to hemoglobin and reduces O₂ affinity.
Which of the following occurs during the chloride shift?
A. Chloride is removed from the erythrocyte.
B. Chloride is exchanged for bicarbonate.
C. Bicarbonate is removed from the erythrocyte.
D. Bicarbonate is removed from the blood.
B. Chloride is exchanged for bicarbonate.
The chloride shift swaps Cl⁻ in for HCO₃⁻ out of red blood cells to maintain charge balance.
Incorrect Answers:
A. Chloride removed: Chloride enters, not exits.
C. Bicarbonate removed: True, but only part of the story—no mention of the exchange.
D. Bicarbonate removed from blood: Bicarbonate exits RBCs, not blood.
A low partial pressure of oxygen promotes hemoglobin binding to carbon dioxide. This is an example of the (BLANK).
A. Haldane effect.
B. Bohr effect.
C. Dalton’s law.
D. Henry’s law.
A. Haldane effect.
The Haldane effect describes how low O₂ increases CO₂ binding to hemoglobin.
Incorrect Answers:
B. Bohr effect: Opposite—describes how high CO₂ lowers hemoglobin’s O₂ affinity.
C. Dalton’s law: Concerns partial pressures of gases, not binding dynamics.
D. Henry’s law: Relates to gas solubility in liquids.
Increased ventilation that results in an increase in blood pH is called (BLANK).
A. Hyperventilation.
B. Hyperpnea.
C. Acclimatization.
D. Apnea.
A. Hyperventilation.
Hyperventilation reduces CO₂, decreasing carbonic acid and increasing blood pH (alkalosis).
Incorrect Answers:
B. Hyperpnea: Increased depth of breathing matched to demand—doesn’t affect pH.
C. Acclimatization: Long-term adaptation to high altitude.
D. Apnea: Temporary cessation of breathing.
Exercise can trigger symptoms of AMS due to which of the following?
A. Low partial pressure of oxygen.
B. Low atmospheric pressure.
C. Abnormal neural signals.
D. Small venous reserve of oxygen.
D. Small venous reserve of oxygen.
During exercise, the body relies on its venous oxygen reserve to supply extra oxygen to tissues. Because this reserve is limited, especially at altitude, exercise can quickly deplete it, triggering symptoms of acute mountain sickness (AMS).
Incorrect Answers:
A. Low PO₂: A contributing factor but not the direct mechanism during exertion.
B. Low atmospheric pressure: The underlying condition but not the exercise trigger.
C. Abnormal neural signals: Not relevant to AMS.
Which of the following stimulates the production of erythrocytes?
A. AMS.
B. High blood levels of carbon dioxide.
C. Low atmospheric pressure.
D. Erythropoietin.
D. Erythropoietin.
Erythropoietin (EPO) is a hormone secreted by the kidneys that directly stimulates red blood cell production.
Incorrect Answers:
A. AMS: Symptom of low oxygen, but doesn’t cause RBC production directly.
B. High CO₂: May affect respiration but doesn’t stimulate erythropoiesis.
C. Low atmospheric pressure: Triggers EPO release but isn’t the direct stimulator.
The olfactory pits form from which of the following?
A. Mesoderm.
B. Cartilage.
C. Ectoderm.
D. Endoderm.
C. Ectoderm.
The olfactory pits develop from ectodermal tissue, which contributes to the formation of the nasal cavities and associated sensory structures.
Incorrect Answers:
A. Mesoderm: Gives rise to muscles, bones, and connective tissue, not olfactory structures.
B. Cartilage: A structural tissue, not a germ layer or primary source of olfactory development.
D. Endoderm: Forms the lining of internal organs like the digestive and respiratory tracts, but not olfactory pits.
A full complement of mature alveoli are present by (BLANK).
A. Early childhood, around 8 years of age.
B. Birth.
C. 37 weeks.
D. 16 weeks.
A. Early childhood, around 8 years of age.
While basic alveoli form before birth, full development and maturation into adult-like alveoli continue until about age 8.
Incorrect Answers:
B. Birth: Only primitive alveoli are present.
C. 37 weeks: Alveolar sacs begin to form, but maturation continues postnatally.
D. 16 weeks: Too early—this is when branching and bronchioles are developing, not mature alveoli.
If a baby is born prematurely before type II cells produce sufficient pulmonary surfactant, which of the following might you expect?
A. Difficulty expressing fluid.
B. Difficulty inflating the lungs.
C. Difficulty with pulmonary capillary flow.
D. No difficulty as type I cells can provide enough surfactant for normal breathing.
B. Difficulty inflating the lungs.
Surfactant, produced by Type II alveolar cells, reduces surface tension. Without it, lungs may collapse, making inflation extremely difficult—this is seen in neonatal respiratory distress syndrome (NRDS).
Incorrect Answers:
A. Difficulty expressing fluid: Fluid is usually cleared passively or absorbed.
C. Pulmonary capillary flow: Generally unaffected by surfactant levels.
D. No difficulty…: Type I cells do not produce surfactant—only Type II do.
When do fetal breathing movements begin?
A. Around week 20.
B. Around week 37.
C. Around week 16.
D. After birth.
A. Around week 20.
Fetal breathing movements begin around week 20, helping develop respiratory muscles and promoting lung development.
Incorrect Answers:
B. Week 37: Lungs are maturing, but breathing movements begin earlier.
C. Week 16: Structural development of bronchioles continues, but breathing movements typically haven’t started.
D. After birth: True breathing begins then, but practice movements start in utero.
What happens to the fluid that remains in the lungs after birth?
A. It reduces the surface tension of the alveoli.
B. It is expelled shortly after birth.
C. It is absorbed shortly after birth.
D. It lubricates the pleurae.
C. It is absorbed shortly after birth.
Remaining lung fluid is absorbed by pulmonary capillaries and lymphatics shortly after birth to allow efficient air exchange.
Incorrect Answers:
A. Reduces surface tension: That’s the role of surfactant, not fluid.
B. Expelled shortly after birth: Some is expelled during labor, but most is absorbed.
D. Lubricates pleurae: Pleural fluid comes from different secretions, not fetal lung fluid.
