The Respiratory System

1. 22 The RespiratorySystem

2. For what metabolic reason does respiration occur? • Solely to increase blood O2 levels • To supply cells with O2 for ATP synthesis and to remove CO2 from the blood • To offload metabolic toxins from body fluids • To decrease blood O2 and increase blood CO2

3. The _____ zone includes the alveoli, while the _______ zone includes the trachea. • conducting; respiratory • transport; ventilation • respiratory; conducting • ventilation; transport

4. Bacteria or other particulate debris contained within inspired air are removed or destroyed by _______. • mucus • vibrissae • stomach acid • all of the above

5. Breathing air through the nose provides multiple functions. What function would be most impacted while breathing dry air? • Warming of the air • Delivering the air to the lungs • Providing a resonance chamber for speech • Humidifying the air

6. Surface area in the nasal cavity is increased by the presence of ________. • olfactory folds • conchae • microvilli • choanae

7. People who have their adenoids removed to cut down on snoring are having their ________ removed. • nasal septum • choanae • conchae • pharyngeal tonsils

8. Occasionally food or liquids will “go down the wrong pipe,” initiating a cough reflex. Which structural barrier has been breached if this happens? • Laryngopharynx • Uvula • Epiglottis • Glottis

9. Men tend to have deeper voices than women because their vocal cords _______. • have a wider opening • are shorter and narrower • have a narrower opening • are longer and thicker

10. The most violent coughing is initiated when foreign objects contact the _____ of the trachea. • carina • trachealis muscle • tracheal rings • mucosa

11. Speech is produced when the _______ of the larynx are moved. • corniculate cartilages • vestibular folds • cricoid cartilages • arytenoid cartilages

12. As the bronchial tree terminates in bronchioles, the principal material comprising their walls is smooth muscle. What functional purpose does this smooth muscle provide? • The walls of the bronchioles provide patent airways to the alveoli. • The walls of the bronchioles allow for gas exchange before air actually enters the alveoli. • The presence of smooth muscle allows the walls of the bronchioles to constrict and provides control over air flow. • Both a and c are true.

13. The respiratory membrane is composed of: • the alveolar sacs and pulmonary arteries. • the alveolar membrane, the capillary wall, and their fused basement membrane. • the fusion of the type I cells and type II cells in the lungs. • the cells found between the alveolar pores.

14. How is it possible to remove a section of lung without damaging neighboring sections? • The bronchopulmonary segments are separated from each other by connective tissue septa. • Surgeons cauterize any freshly cut portion of the lung to seal it. • Lungs are actually comprised of multiple separate structures each served by its own bronchus. • It isn’t possible to perform this type of surgery on the lungs.

15. The pressure in the alveoli is known as __________. • intrapulmonary pressure • intrapleural pressure • transpulmonary pressure • atmospheric pressure

16. If transpulmonary pressure were to suddenly decrease, predict the response by the lungs. • The lungs would not recoil and air would remain trapped in them. • The lungs would adhere to the parietal pleura and would crumple like an accordion. • The lungs would immediately collapse. • The lungs would remain unchanged.

17. _________ is caused by a transpulmonary pressure greater than zero. • A pneumothorax • Inspiration • Apnea • Hyperpnea

18. Air moves into the lungs during inspiration due to the force of __________. • the diaphragm • the abdominal muscles • atmospheric pressure • the external intercostal muscles

19. Air is forced out of the lungs during normal expiration due to _________. • contraction of the diaphragm • elastic recoil of tissues • contraction of bronchioles • contraction of the external intercostal muscles

20. Boyle’s law explains that _________. • at higher temperatures gases are more compressed • gases under low pressure have a lower volume • gases are least soluble when they are in liquid • the pressure of a gas varies inversely with its volume

21. During an asthma attack, bronchioles become severely _______. Taking epinephrine causes them to _______. • constricted; dilate • dilated; constrict • mucus-filled; empty of mucus • both a and c

22. Infant respiratory distress syndrome occurs because premature infants lack the ability to produce _______, which _______. • mucus; traps bacteria • cilia; clear mucus from the trachea • surfactant; lowers surface tension • alveoli; causes them to become hypoxic

23. Even the most forceful exhalation leaves air in the lungs; this is called the ______ and is needed to _______. • tidal volume; acquire adequate O2 • vital capacity; remove adequate CO2 • functional residual capacity; keep alveoli patent • residual volume; keep alveoli patent

24. Two gases contribute to 99% of the total atmospheric pressure. They are ______. • CO2 and O2 • N and O2 • CO2 and H2O vapor • N and CO2

25. The pressure exerted by each gas in a mixture is proportional to its percentage. This is _______. • Dalton’s law of partial pressures • Boyle’s law of partial pressures • Henry’s law of gas percentages • the law of gas proportionality

26. Why is the rate of CO2 exchange roughly equivalent to that of O2 despite its less steep pressure gradient? • CO2 diffuses much more rapidly out of the cells. • CO2 binds to O2 and moves across the respiratory membrane simultaneously. • CO2 is more soluble in water than is O2. • CO2 is actively transported into the alveoli.

27. Hemoglobin molecules are fully saturated when bound to ____ molecule(s) of O2. • one • two • three • four

28. Why is it possible to deliver more O2 to vigorously working cells without increasing respiration rate or cardiac output? • It isn’t: a small decrease in PO2 has very little effect on hemoglobin unloading. • Because once one molecule of O2 is bound to hemoglobin, the other molecules bind much more rapidly. • Because between a PO2 of zero and a PO2 of 40, hemoglobin saturation changes very rapidly and a greater degree of unloading will occur with even small changes in PO2. • Because CO2 released from the vigorously working cells enhances O2 binding to hemoglobin.

29. The Bohr effect describes _________. • a shift to the left in the oxygen-hemoglobin dissociation curve • enhanced cooperation of oxygen binding to hemoglobin in the lungs • a shift to the right in the oxygen-hemoglobin dissociation curve • the conformational structures of hemoglobin as it picks up oxygen in the lungs

30. Red blood cells contain the enzyme _____, which catalyzes the formation of carbonic acid. • carbonic anhydrase • carbon dioxide acidase • oxidase • catalase

31. The chloride shift occurs in red blood cells to: • provide chlorine to the enzyme carbonic anhydrase. • counterbalance the exodus of bicarbonate ions from red blood cells. • counterbalance the exodus of H+ from red blood cells. • convert chloride ions to bicarbonate ions.

32. The _________ is responsible for setting the basic rhythm of breathing. • VRG • DRG • pontine respiratory group • pons

33. ________ is the most potent chemical influencing respiration. • O2 • N • H2O • CO2