Resp System
75. How does the lung parenchyma receive most of its oxygen? a. from the alveolar gases b. from the bronchial arteries/capillaries c. from the pulmonary arteries/capillaries d. from the pulmonary lymphatic system
A A separate arterial supply called the bronchial circulation supplies blood to the airways from the trachea to the bronchioles and to most of the visceral pleurae. The metabolic needs of the lung are comparatively low, and much of the lung parenchyma is oxygenated by direct contact with inspired gas. DIF: Application REF: p. 177
47. Limited, short-term spontaneous ventilation is possible in a patient with a paralyzed diaphragm. a. True b. False c. unable to determine
A Although the diaphragm is the primary ventilatory muscle, it is not essential for survival. Limited, short-term ventilation is possible using accessory muscles, even if the diaphragm is paralyzed. The diaphragm does not actively participate in exhalation. During exhalation, it returns to its resting position during the passive recoil of the lungs and thorax. During forced exhalation, abdominal wall muscles compress the abdominal cavity and increase pressure in the abdominal cavity. This forces the diaphragm upward and compresses the lungs and forces gas from them. The diaphragm performs important functions other than ventilation. It aids in generating high intra-abdominal pressures by remaining fixed while the abdominal muscles contract. This facilitates vomiting, coughing, sneezing, defecation, and parturition. DIF: Application REF: p. 169
17. What percentage of right ventricular output is circulated through the fetal lungs? a. 10% b. 35% c. 75% d. 100%
A As a result, 90% of the blood flow entering the pulmonary artery takes the path of least resistance by shunting through the ductus arteriosus and flows to the aorta. Only 10% flows into the lungs. DIF: Recall REF: p. 156
104. At what point does the trachea branch into two mainstem bronchi? a. carina b. cricoid cartilage c. glottis d. manubrium
A At the base of the trachea, the last cartilaginous ring that forms the bifurcation for the two bronchi is called the carina. The carina is an important landmark that is used to identify the level at which the two mainstem bronchi branch off from the trachea. DIF: Application REF: p. 187
81. What determines the airway diameter in the normal lung? a. balance between sympathetic and parasympathetic tone b. in large part, the amount of patient effort c. activity level of the submucosal glands d. amount of dopamine present in the airway walls
A Both sympathetic and parasympathetic postganglionic efferents innervate the smooth muscle and glands of the airways. They influence the diameter of the airway by causing more or less tension in the smooth muscles that wrap the airway and influence glandular secretion. The combined effects of the parasympathetic and sympathetic nervous activity, which generally oppose each other's action, result in a balanced control of airway diameter. DIF: Application REF: p. 181
126. Which of the following have been shown to injure the alveolar-capillary membrane? 1. excessive pressures 2. excessive tidal volumes 3. increased intracranial pressures 4. pulmonary hypertension a. 1, 2, and 4 b. 2 and 3 c. 4 only d. 1, 2, 3, and 4
A Conditions of pulmonary hypertension (e.g., capillary pressure greater than 30 mm Hg during congestive heart failure and high-altitude pulmonary edema) and excessive tidal volume and airway pressure during positive-pressure ventilation (e.g., tidal volume greater than 6 ml/kg and airway pressures greater than 30 cm H2O) can result in stress failure of the blood-gas membrane. Stress failure results in endothelial and/or type I cell stretching and shearing injuries. DIF: Application REF: p. 200
11. What maintains lung inflation during fetal development? a. fetal lung fluid b. radial tethering c. rigidity of the chest wall d. surfactant
A Fetal lung fluid is constantly produced and keeps the fetal lung inflated at a slight positive pressure with respect to amniotic fluid pressure and is important in promoting normal lung development. DIF: Application REF: p. 153
88. Which of the following help comprise the defense system of the nose? 1. clearance of foreign matter by ciliary action 2. gross filtration by the large hairs of the nasal vestibule 3. impaction of particulate foreign matter on the nasal mucosa 4. laminar flow through the concha a. 1, 2, and 3 b. 2 and 4 c. 3 only d. 1, 2, 3, and 4
A Filtration of inhaled air is carried out by the hair in the anterior portion of the cavity and the sticky mucous membrane that covers the complex surface of the cavity. Filtration is en-hanced by the flow pattern through the nasal cavity. Inspired gas is accelerated to a high ve-locity through the anterior nares. It then changes direction sharply as it enters the internal nasal cavity. This pattern causes particles larger than 10 µm in diameter to impact on the nasal mucosa. Ciliary action or nose blowing then clears these particles. Past the external nares, the cross-sectional area increases. This results in a decrease in gas velocity. Turbu-lence increases because of the narrow convolutions of the passages. Low velocity and turbu-lence combine to remove any remaining particles. DIF: Application REF: p. 183
22. How short could the trachea of a small preterm infant be? a. 2 cm b. 4 cm c. 6 cm d. 8 cm
A In small preterm infants, the trachea may be only 2 cm long and 2 to 3 mm wide DIF: Recall REF: p. 159
42. Compared to a normal diaphragm, contraction of a diaphragm that is low and flat may result in which of the following? a. compression of the thoracic cavity b. enhanced venous return and thus cardiac output c. greater diaphragmatic efficiency d. larger than normal change in thoracic volume
A Increased lung volume causes the diaphragm to flatten out. Contraction of a flattened diaphragm can result in tension on the lower ribs that causes them to be pulled inward, which results in compression of the thoracic cavity. This condition can occur in individuals with severe gas trapping as a result of emphysema or asthma. To compensate for this, these individuals must recruit other muscles to enlarge the thorax. This results in less efficient breathing and excessive muscle work. DIF: Analysis REF: p. 167-168
108. What type of flow is seen in and beyond the terminal bronchioles? a. laminar b. transitional c. turbulent d. varies among individuals
A Low-velocity gas movement at the level of the terminal bronchiole and beyond is physiologically important for two reasons. First, laminar flow develops, which minimizes resistance in the small airways and decreases the work associated with inspiration. Second, low gas velocity facilitates rapid mixing of gases. DIF: Recall REF: p. 191
123. What are the free-wandering phagocytic cells that ingest foreign material in the respiratory zone of the lungs? a. alveolar macrophages b. granular pneumocytes c. type I cells d. type II cells
A Macrophages are another common cell found in the alveolar region. They can move from the pulmonary capillary circulation by squeezing through openings in the alveolar septa and then move out onto the alveolar surface. They are defensive cells that patrol the alveolar region and phagocytize foreign particles and cells (e.g., bacteria). DIF: Recall REF: p. 198
111. What is the major source of respiratory tract secretions in the normal lung? a. bronchial glands b. Clara cells c. goblet cells d. mast cells
A Normally, the respiratory tract produces about 100 ml of mucus per day. Most of the mucus formed in the larger airways is produced by the bronchial glands. DIF: Recall REF: p. 192
90. What is your primary concern if you discover that a patient does not have a gag reflex? a. fear of aspiration of bacteria or food b. that their tonsilar tissues are grossly swollen c. that they will not be able to breathe adequately d. tracheal collapse
A Reflexes of the mouth, pharynx, and larynx help to protect the lower respiratory tract during swallowing. These protective functions can be severely compromised during anesthesia or unconsciousness. Loss or compromise of these important reflexes can result in aspiration of bacteria colonized saliva or food and can cause pulmonary infection and asphyxiation in severe cases. DIF: Application REF: p. 185
46. What is the lowest level on the spinal cord that an injury could cause diaphragmatic impairment or paralysis? a. C3 b. L2 c. S5 d. T4
A Spinal cord injuries at or above the level of the third cervical vertebrae result in diaphragmatic paralysis. DIF: Application REF: p. 169
54. The abdominal muscles can actually contribute to inspiration by contraction at the end of exhalation. a. True b. False c. unable to determine
A The abdominals can also contribute to inspiration by contracting at end-exhalation. This reduces end-expiratory lung volume, so the chest wall can recoil outward, assisting the next inspiratory effort. DIF: Application REF: p. 172
115. What is the common name given to classify the airway from the nares to the terminal bronchioles? a. conducting airways b. respiratory airways c. transitional airways d. upper airway
A The airways from the nares to and including the terminal bronchioles comprise the conducting zone airways, which do not participate in gas exchange. DIF: Application REF: p. 191
77. How does the body compensate for a pulmonary embolus that occludes a branch of the pulmonary artery? a. increased bronchial arterial flow to the area b. increased cardiac output c. pulmonary arteriole and metarteriole vasodilation d. release of prostaglandins to fight inflammation
A The bronchial and pulmonary circulations share an important compensatory relationship. Decreased pulmonary arterial blood pressure tends to cause an increase in bronchial artery blood flow to the affected area. This minimizes the danger of pulmonary infarction, as sometimes occurs when a blood clot (pulmonary embolus) enters the lung. DIF: Application REF: p. 179
26. Infants are more susceptible to profound hypoxemia than are adults. a. True b. False c. unable to determine
A The combination of a reduced FRC and high oxygen consumption in infants renders them more susceptible to profound hypoxemia in situations that further disturb ventilation, lung volume, and/or ventilation/perfusion matching. DIF: Application REF: p. 162
9. During which phase of fetal development do mature alveoli appear? a. alveolar b. canalicular c. pseudoglandular d. saccular
A The development of mature alveoli, accompanied by capillary proliferation within the walls, marks the final phase of lung development and is known as the alveolar period. DIF: Application REF: p. 149
48. Which accessory muscles are active during resting and active inspiration and pull up on all the ribs expanding the thorax? a. external intercostals b. internal intercostals c. scalenes d. sternocleidomastoids
A The external intercostals (Figure 8-22) originate on the upper ribs and attach to the lower ribs. The fibers of these muscles run at an oblique angle between the ribs. When they generate tension, they lift the ribs upward and cause the thoracic cavity to enlarge the thorax. DIF: Application REF: p. 167
100. Changes in the tension on the vocal cords, allowing phonation, are produced by the interaction of the laryngeal muscles and the movement of which cartilage? a. arytenoids b. corniculates c. cricoid d. cuneiforms
A The laryngeal component of speech is called phonation. It requires the adjustment of vocal cord tension and position relative to one another. The action of the posterior cricoarytenoid muscles causes the arytenoid cartilages to rotate and opens the vocal cords. Closure of the vocal cords is carried out by rotating the arytenoids in the opposite direction through the action of the lateral cricoarytenoid and oblique arytenoid muscles. DIF: Application REF: p. 187
61. About how far do the normal adult lungs extend above the clavicles? a. 2 cm b. 3 cm c. 4 cm d. 5 cm
A The lungs extend from the diaphragm to a point 1 to 2 cm above the medial third of the clavicles. DIF: Recall REF: p. 174
109. What is the most common cell type found in the mucosa of the larger airways? a. pseudostratified ciliated columnar epithelium b. pseudostratified ciliated cuboidal epithelium c. stratified ciliated squamous epithelium d. stratified unciliated serous endothelium
A The most common type of epithelia is the numerous pseudostratified, ciliated, columnar epithelia. DIF: Application REF: p. 191
19. What strong stimulus to the infant provides the impetus for the first breath? a. acidosis b. exposure to warmth c. fright from passing through the birth canal d. high PaO2
A The newborn infant is stimulated by new tactile and thermal stimuli, all of which stimulate breathing. In addition, as placental gas transfer is suddenly interrupted, the newborn quickly becomes hypoxemic, hypercapnic, and acidotic. | : 4 DIFF: Application DIF: Application REF: p. 156
127. Identify the non-primary function(s) of the respiratory system: a. filter out inhaled contaminants, various chemicals, and small blood clots b. exchange of gases between blood and tissues c. continuous absorption of oxygen and excretion of carbon dioxide d. transport oxygenated blood to the tissues
A The primary role of the respiratory system is breathing, external respiration (the continuous absorption of oxygen and the excretion of carbon dioxide), and the support of internal respiration, which is the exchange of gases between blood and tissues. The respiratory system is also equipped to filter out inhaled contaminants, while warming and humidifying inspired gas and simultaneously filter out various chemicals and small blood clots that are deposited or formed in the blood. DIF: Application REF: p. 148
24. What is unique regarding the blood supply to the lung? a. It receives blood from right and left ventricles. b. It requires no dedicated blood supply as it exists in a gas environment. c. Pulmonary venous drainage contributes to the normal anatomic shunt. d. The pulmonary arteries are the primary source of oxygen for lung structures.
A The respiratory system is a unique organ in that it receives a double blood supply: one from the left ventricle and one from the right ventricle. DIF: Application REF: p. 160
1. What is the primary purpose of the respiratory system? a. continuous absorption of oxygen and excretion of carbon dioxide b. filtering to prevent allergens and microbes from reaching the lungs c. transport oxygenated blood to the tissues d. warm and humidify inspired gas
A The respiratory system's primary function is the continuous absorption of oxygen and the excretion of carbon dioxide. DIF: Application REF: p. 148
33. What is the name of the external landmark that identifies the point at which the trachea branches into the right and left mainstem bronchi? a. angle of Louis b. cricoid cartilage c. suprasternal notch d. xiphoid process
A The sternal angle is an external marker of the point where the trachea divides into the left and right mainstem bronchi. DIF: Recall REF: p. 164
50. As ventilatory muscles, the sternocleidomastoids do which of the following? a. They elevate the upper chest, increasing chest anteroposterior diameter. b. They levate the ribs and decrease chest anteroposterior diameter. c. They increase lateral chest movement during inspiration. d. They llower the sternum, thus increasing chest anteroposterior diameter.
A The sternocleidomastoid muscles can function to lift the upper chest. They receive nerve impulses from branches of the accessory nerves (cranial nerve XI) and cervical nerves C1 and C2. These muscles are active during forceful inspiration and become visible as thick bands on either side of the neck during the inspiratory phase in an individual who is in respiratory distress. This motion increases the anteroposterior diameter of the chest. DIF: Application REF: p. 171
41. How far is the diaphragm pulled down during tidal breathing? a. 1 to 2 cm b. 3 to 5 cm c. 6 to 8 cm d. 8 to 10 cm
A When the muscle fibers of the diaphragm are tensioned during inspiration, the dome of the diaphragm is pulled down 1 to 2 cm. DIF: Recall REF: p. 167
117. Which of the following describes an acinus? a. Each acinus is comprised of five terminal respiratory units. b. It consists of all structures distal to a terminal bronchiole. c. It is composed of the smaller conducting airways. d. It is the transitional portion of the lung between conduction and respiration.
B A single terminal bronchiole supplies a cluster of respiratory bronchioles. Collectively, this unit is referred to as the acinus. DIF: Recall REF: p. 195
119. Where are the largest alveoli found in the lung? a. acinus b. apices c. bases d. middle
B Alveoli found in the apical regions of the vertical lung have greater diameters than those in the basal regions as a result of the gravitational effects. Those in the basal regions are partially collapsed as a result of the weight of the organ. DIF: Application REF: p. 195
130. Which phospholipid ratio would indicate a neonate with a low risk of developing respiratory distress syndrome (RDS)? a. L/S ratio of 1 b. L/S ratio of 2 or more c. L/S ratio of less than 1.5 d. L/S ratio of less then 1
B An L/S ratio of 2 or more indicates a relatively low risk for the development of respiratory distress syndrome, while an L/S ratio of less than 1.5 is associated with a high risk. DIF: Application REF: p. 153
83. What is the name of the reflex associated with the sensory stimulation of the pulmonary stretch receptors that stimulates a deeper breath upon inspiration? a. carotid sinus b. Head's paradoxical c. Hering-Breuer d. vagovagal
B Another reflex that is associated with stretch receptor activity is Head's paradoxical reflex. This reflex stimulates a deeper breath rather than inhibiting further inspiration. It may be the basis for occasional deep breaths or gasps. Deep breaths or sighs occur with normal breathing, presumably preventing alveolar collapse. Head's reflex may also be responsible for gasping in newborn infants as they progressively inflate their lungs. DIF: Recall REF: p. 181
8. The fetus is potentially viable if born at the end of which stage of development? a. alveolar b. canalicular c. pseudoglandular d. saccular
B At the end of the canalicular period (24 to 26 weeks of gestation), the fetus, if born, is capable of sufficient gas exchange and is viable if supported completely with an artificial airway, oxygen, ventilatory support, and surfactant administration. DIF: Application REF: p. 149
76. Via what pathway does much of the bronchial venous drainage occur? a. bronchial veins emptying into the inferior vena cava b. bronchopulmonary veins emptying into pulmonary veins c. direct connections between bronchial and pulmonary arteries d. thebesian venous drainage into the heart chambers
B Bronchial venous blood drains through the azygos, hemiazygos, and intercostal veins to the right atrium, and some drains through the pulmonary capillaries to the pulmonary veins and to the left atrium. DIF: Application REF: p. 178
4. The human genome contains _____ pairs of chromosomes. a. 16 b. 23 c. 46 d. 50
B DNA is organized into 23 pairs of supercoiled masses that are called chromosomes. DIF: Recall REF: p. 150
6. Developmental morphogenesis of the human respiratory system can be categorized into: a. three periods b. five stages c. 6 weeks d. 40 weeks
B Figure 8-1 shows the various stages of lung development, and Table 8-1 summarizes the major developmental events in each phase. DIF: Application REF: p. 149
44. The diaphragm is innervated by which of the following nerves? a. glossopharyngeal b. phrenic c. seventh cranial d. vagus
B Functionally, the diaphragm is divided into a right and left hemidiaphragm. Each hemidiaphragm is innervated by a phrenic nerve that arises from branches of spinal nerves C3, C4, and C5. DIF: Recall REF: p. 160
92. Into what structure do the eustachian tubes drain? a. larynx b. nasopharynx c. oropharynx d. vestibule
B In the lateral nasopharynx, there are two openings into the left and right eustachian tubes that link the upper airway with the middle ear (Figure 8-36). The eustachian tubes drain fluid out of the middle ear and allows gas to move in or out of the middle to equalize pressure on either side of the tympanic membrane. DIF: Recall REF: p. 185
43. What pulmonary disorder could lead to acute flattening of the diaphragm? a. adult respiratory distress syndrome b. asthma c. atelectasis d. aneumonia
B Increased lung volume causes the diaphragm to flatten out. This condition can occur in individuals with severe gas trapping as a result of emphysema or asthma. DIF: Application REF: p. 168
36. The intercostal arteries, veins, and nerves run through which of the following? a. costal groove on the top of each rib b. costal groove on the bottom of each rib c. fibers of the intercostal musculature d. surface of the parietal pleura
B Just below each rib are a thoracic artery, vein, and nerve that supply blood flow and nerve communications to that region of the chest wall (Figure 8-17). DIF: Recall REF: p. 173
By which of the following routes does blood flow through the umbilical cord between the placenta and the fetus? a. one umbilical vein and one umbilical artery b. one umbilical vein and two umbilical arteries c. two umbilical veins and one umbilical artery d. two umbilical veins and two umbilical arteries
B Maternal blood flows into the intervillous space through the spiral arteries, while fetal blood is supplied to the villi from two umbilical arteries. Oxygenated fetal blood leaves the chorionic villi capillaries through placental venules and returns to the fetus through a single umbilical vein. DIF: Application REF: p. 154
112. Identify functions of airway mucus in the normal lung. 1. increased mucus production decreases bronchospasm 2. protect the airways from excessive water loss 3. shield the airway from toxic particles 4. trap inhaled contaminants a. 1, 2, and 3 b. 2, 3, and 4 c. 1 and IV4 d. 3, and 4
B Mucus functions to protect the underlying tissue. It helps to prevent excessive amounts of water from moving into and out of the epithelia. It shields the epithelia from direct contact with potentially toxic materials and microorganisms. It acts like sticky flypaper to trap particles that make contact with it. This makes mucus an important part of the pulmonary defenses. DIF: Application REF: p. 193
10. Which of the following is an index commonly used to determine relative lung maturity? a. FRC/TLC ratio b. L:S ratio c. RQ ratio d. SP-A
B Quantification of these phospholipids (the L:S ratio and PG concentration) provides a predictive index of the lung maturity in the fetus before birth and the risks of developing respiratory disease. DIF: Application REF: p. 153
34. Which of rib pairs connect directly to the sternum? a. 1 through 4 b. 1 through 7 c. 1 through 12 d. 11 through 12
B Rib pairs 1 through 7 are known as the true ribs because they are attached directly to the sternum. DIF: Recall REF: p. 165
106. What portion of the left lung corresponds anatomically to the middle lobe of the right lung? a. cardiac notch b. lingula c. medial segment d. superior segment
B See Table 8-8. DIF: Application REF: p. 190
107. Which of the following statements about the terminal bronchioles is true? a. They are generally five divisions below the segmental bronchi. b. They are the smallest of the purely conducting airways. c. They average 3 to 4 mm in diameter. d. They have well-defined and predictable amounts of cartilage.
B Terminal bronchioles are the smallest conducting airways and function to supply gas to the respiratory zone of the lung. DIF: Application REF: p. 191
103. The adult trachea is approximately how long? a. 5 to 8 cm b. 10 to 12 cm c. 16 to 18 cm d. 20 to 24 cm
B The adult trachea is approximately 12 cm long and has an inner diameter of about 2.0 cm. DIF: Recall REF: p. 187
57. What is the name given to the acute angle formed by the costal pleura joining the diaphragmatic pleura? a. angle of Louis b. costophrenic angle c. diaphragmatic groove d. oblique fissure
B The angles where the costal parietal pleura joins the diaphragmatic parietal pleura is known as the costophrenic angle. DIF: Application REF: p. 173
5. Which chromosome has been found to carry the defective gene responsible for the development of cystic fibrosis? a. 1 b. 7 c. 15 d. 23
B The defective gene that is responsible for defective CFTR is located on chromosome 7 in the q31.2 region and has been found to be mutable in more than 1500 different ways. DIF: Recall REF: p. 191
38. Which of the following muscles are considered primary muscles of ventilation? 1. diaphragm 2. intercostals 3. scalenes 4. Sternomastoid a. 1, 3, and 4 b. 1 and 2 c. 3 only d. 1, 2, 3, and 4
B The diaphragm and intercostal muscles are the primary muscles of ventilation. DIF: Recall REF: p. 166
32. Where does the sternal angle lie? a. at the depression in the body of the sternum to which the clavicles attach b. at the join between the manubrium and sternal body c. at the superior edge of the sternum d. where the xiphoid process connects to the sternum
B The fused connection between the manubrium and the body is known as the sternal angle. It is also known as the angle of Louis. DIF: Recall REF: p. 164
52. Which accessory muscles of ventilation work to pull the ribs closer together? a. external intercostals b. internal intercostals c. scalenes d. sternocleidomastoids
B The internal intercostal muscles (Figure 8-22) lie between the ribs and just behind the external intercostal muscles. They originate along the inferior border of the upper ribs and insert into the superior border of the lower ribs. The muscle fibers of the internal intercostal muscles run downward and less obliquely than the external intercostal muscle fibers. This orientation causes these muscles to pull the ribs together, which results in compression of the thoracic cavity. DIF: Application REF: p. 171
51. When a COPD patient leans forward braced in a tripod position, this lends particular advantage to which accessory muscles of inspiration? a. external intercostals b. pectoralis c. scalenes d. sternocleidomastoids
B The major and minor pectoralis muscles are broad fan-shaped muscles of the upper anterior chest (Figure 8-25). The pectoralis major originates on the humerus and inserts onto the clavicle and sternum. The pectoralis minor originates on the scapula and inserts on the anterior portions of ribs 3 through 5. When these muscles receive impulses from the pectoral nerves, they normally function to adduct the arms in a hugging motion. They are also capable of generating some anterior thoracic lift when the arms are braced on a surface in front of a subject. Those individuals who suffer with chronic shortness of breath often utilize these muscles by sitting in a "tripod" position. This is performed by sitting upright and leaning forward with both arms braced on a table. DIF: Application REF: p. 171
99. What is the space that separates the true vocal cords? a. epiglottis b. glottis c. vallecula d. vestibule
B The opening formed between the vocal cords is called the glottis. DIF: Recall REF: p. 186
60. Why is the left lung narrower than the right lung? a. Liver compresses the left lung. b. Mediastinal organs push laterally into the left hemithorax. c. There is poorer blood flow during fetal development. d. There is upward pressure of the abdominal contents.
B The organs within the mediastinum bulge into the left hemithorax, resulting in a narrower and slightly smaller left lung. DIF: Application REF: p. 174
89. What are the vascularized lymphoidal tissues that have a particularly active immunological role in children? a. lingual tonsils b. palatine tonsils c. pharyngeal tonsils d. superior turbinates
B The palatine tonsils are vascularized lymphoidal tissues that play an immunologic role, especially in childhood. DIF: Application REF: p. 184
118. What is called the "functional unit of the lungs"? a. only the alveoli b. acinus c. alveolar-capillary membranes d. terminal bronchioles
B The primary lobule or acinus forms the functional unit of the lungs. DIF: Application REF: p. 195
67. The pulmonary arterial circulation does which of the following? 1. delivers oxygenated blood back to the heart 2. delivers unoxygenated blood to the lungs 3. originates on the left side of the heart 4. originates on the right side of the heart a. 1 and 4 b. 2 and 4 c. 1 and 3 d. 2 and 3
B The pulmonary circulation arises from the right heart (Figure 8-30) and carries the entire cardiac output through the lung each minute. Oxygen-reduced systemic venous blood returns to the right heart via the inferior and superior venae cavae. This blood is pumped to the lungs by the right ventricle through the pulmonic semilunar valve and on to the trunk of the pulmonary artery. DIF: Application REF: p. 175
16. Which factors contribute to maintaining a patent ductus arteriosus during fetal life? 1. large amounts of fetal hemoglobin 2. low PaO2 3. presence of LDH 4. presence of prostaglandins a. 1, 2, and 3 b. 2 and 4 c. 3 only d. 1, 2, 3, and 4
B The relatively low PO2 and various prostaglandins in fetal blood cause the ductus arteriosus, a muscular vessel attached to the trunk of the pulmonary artery and the aorta, to dilate and the pulmonary arteries to constrict. DIF: Application REF: p. 156
31. What is the name of the upper portion of the sternum? a. angle of Louis b. manubrium c. vertebral process d. xiphoid process
B The sternum is a long, vertical flat bone found on the anterior side (Figure 8-18). It is comprised of three bones including the manubrium which comprises the upper portion. DIF: Recall REF: p. 164
113. What is the name given to the action produced by the forward stroking of millions of cilia? a. coughing b. mucociliary escalator c. mucus stroking d. the wave
B The stroking action of millions of cilia propels the surrounding mucus at a speed of about 2 cm per minute. This action is commonly referred to as the mucociliary escalator. DIF: Recall REF: p. 194
69. Which of the following describes a function of pulmonary circulation? a. breakdown of angiotensin II b. filtering of blood clots c. production of erythropoietin d. regulation of breathing
B The third function is nonrespiratory and participates in the production, processing, and clearance of a large variety of chemicals and blood clots. DIF: Application REF: p. 177
116. What is normal amount of anatomic dead space found in a healthy lung? a. 1 ml/kg ideal body weight b. 2 ml/kg ideal body weight c. 3 ml/kg ideal body weight d. 4 ml/kg ideal body weight
B These airways constitute the anatomic dead space of the respiratory system that is rebreathed with each breath. In the adult human, the volume filling the airways of the anatomic dead space is approximately 2 ml/kg of lean body weight, or about 150 ml in the typical adult. DIF: Recall REF: p. 195
63. What will happen when the lung is surgically removed from the thorax? a. The lung will appear to undergo no change. b. The lung will collapse. c. The lung will expand. d. The response of the lung will depend on its age and pathology.
B When a lung is removed from the chest cavity, it quickly collapses to a smaller size. DIF: Application REF: p. 175
70. Compared with the systemic circulation, pressure in the normal pulmonary circulation is: a. higher b. lower c. the same
B While the entire cardiac output passes through both pulmonary and systemic circuits, the pulmonary circulation offers much lower resistance and, as a result, has a much lower blood pressure. DIF: Application REF: p. 177
25. What is the physiologic result of the infants' more compliant thorax compared with that of an adult? a. It is easier for infants to breathe. b. Their functional residual capacity is reduced based on ideal body weight (IBW). c. They breathe larger tidal volumes based on IBW. d. They have less of a tendency to develop atelectasis.
B With a more compliant thorax, the resultant balance of these static forces in the infant favors a reduced FRC and total lung capacity (TLC). Proportionately lower lung volumes in the infant can lead to early airway closure, atelectasis, ventilation/perfusion mismatch, shunting, and resultant hypoxemia. DIF: Application REF: p. 162
15. In the fetal heart, the foramen ovale allows blood to flow between which two structures? a. bypass the liver and enter the inferior vena cava b. pulmonary artery to aortic arch c. right atrium to left atrium d. right atrium to left ventricle
C Approximately 50% of this blood is shunted from the right atrium into the left atrium through an opening in the interatrial septum called the foramen ovale. DIF: Application REF: p. 156
74. How does the lung respond to regional lung hypoxia? a. bronchial artery vasoconstriction b. bronchial artery vasodilation c. pulmonary artery vasoconstriction d. pulmonary artery vasodilation
C Areas of regional lung hypoxia, as the result of reduced ventilation, congestion, and/or airway obstruction, can result in local pulmonary arterial vasoconstriction and cause blood flow to be shifted from these areas toward areas of higher oxygen content and pulmonary vasodilation. DIF: Application REF: p. 177
73. How would lung perfusion in a "zone 1" area best be described? a. increased b. normal or average c. reduced
C Areas that experience higher airway pressure (e.g., during positive pressure ventilation) that equal or exceed local arteriole and capillary pressure will have reduced blood flow as a result of the opposing airway pressure (zone 1 airways). DIF: Application REF: p. 177
72. Which of the following statements is NOT true regarding the pulmonary circulation? a. Pulmonary blood flow is highly dependent on gravity. b. The pulmonary circulation is a low-pressure system. c. Toward the top of the upright lung, blood flow is high. d. Toward the top of the upright lung, blood flow is low.
C As a consequence of having a low blood pressure and being susceptible to gravity, blood flow is much higher in the lung bases in resting upright subjects. Gravity-related effects also occur in recumbent positions but are less pronounced. DIF: Application REF: p. 177
7. The fetus is potentially viable if born prematurely after how many weeks of gestation? a. 12 to 16 weeks b. 18 to 20 weeks c. 24 to 26 weeks d. 28 to 32 weeks
C At the end of the canalicular period (24 to 26 weeks of gestation), the fetus, if born, is capable of sufficient gas exchange and is viable if supported completely with an artificial airway, oxygen, ventilatory support, and surfactant administration. DIF: Application REF: p. 149
114. Which of the following can impair or inhibit ciliary activity? 1. drying of the respiratory tract mucosa 2. exposure to smoke 3. parasympatholytic drugs a. 1 and 2 b. 1 only c. 1, 2, and 3 d. 2 and 3
C Ciliary beating can be effectively slowed or even stopped if the viscosity of the sol layer is increased by exposure to dry gas. Ciliary motion is also stopped following exposure to smoke, high concentrations of inhaled oxygen, and drugs like atropine. DIF: Application REF: p. 194
18. During a vaginal delivery, what facilitates the removal of fetal lung fluid from the pulmonary system? a. high PaO2 b. low intrapulmonary pressures c. thoracic compression d. triaging of core functions
C During normal vaginal delivery, approximately one third of the lung fluid is cleared by compression of the thorax in the birth canal. DIF: Application REF: p. 156
93. What results in partial or total obstruction of the airway in an unconscious patient? a. closed mouth coexistent with nasal congestion b. epiglottis relaxes and occludes the laryngeal opening c. relaxation of tongue and hypopharyngeal muscles. d. the uvula occluding the airway
C During unconsciousness, the muscles of the tongue and hypopharynx can relax and allow the tongue and other soft tissues to collapse and occlude the opening of the hypopharynx. This condition can result in partial to complete blockage of the upper airway and limit air movement to and from the respiratory tract. This is a primary cause of obstructive sleep apnea. DIF: Application REF: p. 185
58. What will most commonly blunt the costophrenic angle as seen on chest radiograph in an upright individual? a. air b. bile c. excess fluids d. liver on the right, intestines on the left
C Excess fluids between the visceral and parietal pleura tend to pool here in an upright individual. This causes the angle to appear blunted or flattened to 90 degrees when viewed in the chest radiograph. DIF: Application REF: p. 173
14. What would be a normal P50 for a fetus? a. 10 b. 15 c. 20 d. 25
C Figure 8-6 illustrates how the increased oxygen affinity is manifested by a leftward shift of the fetal oxyhemoglobin dissociation curve. The P50 (PO2 that saturates 50% of the hemoglobin) is 6 to 8 mm Hg less than adult hemoglobin (HbA), which indicates the degree of the shift toward higher affinity. DIF: Application REF: p. 155
94. What is a primary function of the larynx? a. cover the glottic opening during forced expiration b. house Waldeyer's ring of tonsilar material for airway defense c. protect airway during eating or drinking d. provide a common passageway for food and gas
C Generally, it functions to protect the respiratory tract during eating and drinking and in phonation. DIF: Application REF: p. 185
96. What is the only complete circular cartilage of the larynx? a. arytenoid b. corniculate c. cricoid d. Thyroid
C Just below the thyroid cartilage is the cricoid cartilage, which is the only laryngeal structure that forms a complete ring of cartilage around the airway and is the narrowest region of the upper airway in infants. DIF: Recall REF: p. 185
125. To what does the term "faster-weaker" refer when discussing the alveolar-capillary membrane? a. portion of the alveolar-capillary membrane that is average in thickness b. shortest airways in the acinus, which allow fast gas exchange c. thinnest portion of the alveolar-capillary membrane d. thickest portion of the alveolar-capillary membrane
C On one side of the alveolar wall, the type I cell and capillary endothelial cells lie close to-gether with a thin interstitial space. This part of the blood-gas barrier is, on average, 0.2 to 0.3 µm thick and it is where the alveolar capillary bulges into the alveolar space. On the oth-er side, where there is a thicker interstitial space with greater fiber, matrix, and nuclear ma-terial content, the barrier can be more than 3 to 10 times thicker. This functionally results in "faster-weaker" and "slower-stronger" diffusion sides of the blood-gas barrier. DIF: Application REF: p. 200
82. What is the name of the negative feedback reflex associated with the termination of inspiration? a. carotid sinus b. Head's paradoxical c. Hering-Breuer d. vagovagal
C Pulmonary stretch receptors progressively discharge during lung inflation and are linked to inhibition of further inflation. This is a type of negative feedback known as the inflation reflex or the Hering-Breuer inflation reflex. DIF: Recall REF: p. 181
35. What are rib pairs 11 and 12 known as? a. false ribs b. faux ribs c. floating ribs d. true ribs
C Rib pairs 11 and 12 are called floating ribs because they are not attached to the sternum. DIF: Application REF: p. 165
37. What does the "pump handle" movement of rib pairs 2 through 7 achieve? a. anchor of the upper chest for diaphragmatic contraction b. diminish of the energy wasted by inefficient muscular contraction c. increase in the anteroposterior diameter of the chest d. increase in the lateral dimensions of the chest
C Ribs 2 through 7 move simultaneously about two axes (Figure 8-20). As each rib rotates about the axis of its neck, its sternal end rises and falls. This movement increases the anteroposterior thoracic diameter in what is commonly referred to as a "pump handle"like motion. DIF: Application REF: p. 166
124. What intercommunicating channels permit collateral ventilation between adjacent alveoli and primary lobules? 1. bronchial anastomoses 2. canals of Lambert 3. pores of Kohn 4. terminal bronchioles a. 1, 2, and 3 b. 1 and 4 c. 2 and 3 d. 1, 2, 3, and 4
C Small openings are located in the alveolar septa. Some of the openings allow gas to move from one alveolus to another. These are called the pores of Kohn. Other openings connect alveoli with secondary respiratory bronchioles. These passageways are called the canals of Lambert. All of these alveolar openings and passageways facilitate the collateral movement of gas and help maintain alveolar volume. DIF: Recall REF: p. 198
120. What type of alveolar cells cover over 90% of the surface area of the alveolar-capillary membrane? a. alveolar macrophages b. granular pneumocytes c. type I cells d. type II cells
C The alveolar septa are covered with extremely flat squamous epithelia called type I pneumocytes (Figure 8-54). While they represent only about 8% of all the cells found in the alveolar region, the type I cells cover about 93% of the alveolar surface. DIF: Recall REF: p. 197
128. What happens throughout fetal period? a. All major organs begin their development. b. Some of the major organs complete their development. c. Organs continue to develop and refine their structure and function. d. Gas exchange begins.
C The fetal period occurs during the remaining 32 weeks of gestation. During this period, the organs continue to develop and refine their structure and function. DIF: Application REF: p. 148
27. Infants can generate auto-PEEP by which of the following methods? a. active expiration b. increased diaphragmatic excursion c. laryngeal braking d. Retractions
C The infant, especially one in distress, can actively end expiration and begin the next inspiratory phase to cause gas trapping, which leads to elevated FRC and better ventilation/perfusion matching. This can be accomplished actively using their diaphragm during exhalation to slow expiration and to adduct (close) their vocal cords and narrow the glottis. The combination of these two maneuvers effectively regulates volume in the lung and dynamically elevates the FRC. The narrowing of the glottis or larynx during exhalation is referred to as "laryngeal braking." | 5 DIFF: Application DIF: Application REF: p. 162
30. What is the name of the thin serous membrane that covers the inner layer of the thoracic wall? a. cupula b. mesothelioma c. parietal pleura d. visceral pleura
C The inner layer of the thoracic wall is lined with a serous membrane called the parietal pleura. DIF: Recall REF: p. 164
28. Running vertically down each hemithorax anteriorly is an imaginary line that is used as an anatomical landmark. What is that line called? a. anterior axillary line b. midaxillary line c. midclavicular line d. midsternal line
C The left and right midclavicular lines are parallel to the midsternal line. These are drawn through the midpoints of the left and right clavicles, respectively (Figure 8-13). DIF: Application REF: p. 62
87. Which of the following is NOT a primary function of the nasal cavity? a. conduction of gases b. filtration and defense c. gas exchange d. heat and humidify
C The primary functions of the nasal cavity are to serve as a gas passageway, and to filter, humidifier, and heat inhaled gases. DIF: Application REF: p. 183
29. What is the function of the thorax? a. facilitate digestion b. heat, humidify, and filter gases c. protect the vital organs d. vocalization
C The thorax is a cone-shaped cavity that houses the lungs and the contents of the mediastinum (Figure 8-16). It functions to protect the vital organs within and has the capability of changing shape to enable air to be moved into and out of the lungs. DIF: Application REF: p. 163
85. The upper respiratory tract traditionally ends at what point? a. branching of the trachea into right and left main-stem bronchi b. hypopharynx c. inferior border of the larynx d. the end of the conducting airways
C The upper respiratory tract is defined as those airways starting at the nose and mouth and that extend down to the trachea (Figure 8-36). DIF: Application REF: p. 181
65. What forces establish the subatmospheric pressure found in the pleural space? a. contraction of accessory muscles of inspiration b. contraction of expiratory muscles c. equal opposing tendency of the chest wall to expand and lung to collapse. d. effect of gravity, particularly at the base of the lungs
C This tendency of the lung to collapse is counteracted by the thoracic wall's tendency to spring outward and to hold the lung inflated. The "tension" developed by these two opposing tendencies results in development of subatmospheric intrapleural pressure. DIF: Application REF: p. 175
49. Which of the following is the most important ventilatory function of the scalene muscles? a. Activate if intrathoracic pressure falls to -40 cm H2O. b. Elevate and fix the first seven ribs. c. Lift upper chest particularly during times of high ventilatory demand. d. Support the trachea within the thorax during heavy exercise.
C Three pairs of scalene muscles (scalenus anterior, scalenus medius, and scalenus posterior) arise from the lower five or six cervical vertebrae and insert on the clavicle and first two ribs (Figure 8-23). They lift the upper chest when active. DIF: Application REF: p. 176
121. Pulmonary surfactant is secreted by which type of lung cells? a. alveolar macrophages b. type I cells (pneumocytes) c. type II pneumocytes d. type III pneumocytes
C Type II cells do not function as gas exchange membranes like the type I cells. They manufacture surfactant, store it in vesicles called lamellated bodies, and secrete it onto the alveolar surface. DIF: Recall REF: p. 198
53. Which of the muscles below when stimulated will contract and push up on the diaphragm? 1. external intercostals 2. external obliques 3. internal obliques 4. rectus abdominous a. 1, 2, and 3 b. 1 and 4 c. 2, 3, and 4 d. 1, 2, 3, and 4
C When the abdominal wall muscles contract, they compress the abdominal cavity. This forces the diaphragm upward and compresses the thoracic cavity. The abdominal muscles include pairs of external oblique, internal oblique, transverse abdominis, and rectus abdominous muscles (Figure 8-27). DIF: Application REF: p. 171
71. Pressures in the pulmonary circulation are lower than those in the systemic circulation because of what characteristic of the pulmonary circulation? a. higher resistance than the systemic circulation b. less blood flow than the systemic circulation c. lower resistance than the systemic circulation d. more blood flow than the systemic circulation
C While the entire cardiac output passes through both pulmonary and systemic circuits, the pulmonary circulation offers much lower resistance and, as a result, has a much lower blood pressure. DIF: Application REF: p. 177
13. Abnormalities of the placenta that can cause intrauterine growth retardation or fetal asphyxia include which of the following? 1. abnormal implantation of the placenta 2. separation of the placenta from the uterine wall 3. decreased placental blood flow a. 2 and 3 b. 1 and 2 c. 1 and 3 d. 1, 2, and 3
D Abnormal implantation of the placenta, tearing of the placenta from the uterine wall, or decreased placental blood flow can retard intrauterine growth and in severe cases can cause fetal asphyxia and increases the risk for brain damage and respiratory distress in the immediate postnatal period. DIF: Application REF: p. 154
80. What is the affect of damage to the recurrent laryngeal nerves? a. diaphragmatic paralysis b. pulmonary circulatory failure c. inactivation of pulmonary surfactant production d. vocal cord impairment or paralysis
D Damage to laryngeal nerves can cause unilateral or bilateral vocal cord paralysis, depending on which branches are involved. This may result in hoarseness, loss of voice, and an ineffective cough. DIF: Application REF: p. 180
40. Approximately what percent of the normal changes in thoracic volume during quiet inspiration is due to the action of the diaphragm? a. 15 b. 25 c. 50 d. 75
D During quiet breathing, the diaphragm is responsible for approximately 75% of the change in thoracic volume. DIF: Recall REF: p. 167
62. Which of the following statements describes a normal adult lung? a. The left lung is bisected by two fissures. b. The left lung has an upper, a middle, and a lower lobe. c. The right lung has only an upper and a lower lobe. d. The right lung has three lobes and two fissures.
D Each lung is divided into two or three lobes (Figure 8-28), which are separated by one or more fissures. The right lung has upper, middle, and lower lobes. The left lung has only an upper and a lower lobe. Both lungs have an oblique fissure that begins on the anterior chest at approximately the sixth rib at the midclavicular line. These fissures extend laterally and upward until they cross the fifth rib on the lateral chest in the midaxillary line. The fissures continue on the posterior chest to approximately the third thoracic vertebra. The right lung also has a horizontal or "minor" fissure that separates the upper and middle lobes. DIF: Recall REF: p. 175
20. Which of the following would NOT promote transition from fetal circulation to a normal extrauterine circulatory pattern? a. closure of the foramen ovale b. constriction of the ductus arteriosus c. decreased pulmonary vascular resistance d. decreased systemic vascular resistance
D Figure 8-9 summarizes the major cardiopulmonary changes that take place during the transition from the fluid-filled lung to an air filled lung. As the lung expands with air and gas exchange starts within the lung, pulmonary blood PO2 increases, PCO2 decreases, and the pH rises. This results in pulmonary vasodilation, lower pulmonary vascular resistance, and constriction of the ductus arteriosus. This facilitates greater blood flow through the pulmonary circulation. Ductus arteriosus closure is further stimulated by the loss of maternal prostaglandins. The combination of increasing alveolar air content and constriction of the ductus arteriosus promotes progressive improvement in the matching of ventilation and blood flow, which, in turn, increases the PO2 and decreases the PCO2 of blood leaving the lungs. Cessation of umbilical and placental blood flow, following the clamping of the umbilical cord, causes closure of the ductus venosus and a rapid rise in systemic vascular resistance. The combination of the above events establish a normal extrauterine circulatory pattern. DIF: Application REF: p. 156
45. The nerves that innervate the diaphragm arise from which area? a. lumbar region of the spine b. sacral vertebrae 4 and 5 c. spinal plexuses at T2 to T11 d. spinal nerves C3 to C5
D Functionally, the diaphragm is divided into a right and left hemidiaphragm. Each hemidiaphragm is innervated by a phrenic nerve that arises from branches of spinal nerves C3, C4, and C5. DIF: Recall REF: p. 167
21. What factor contributes to increased likelihood of an upper airway obstruction in an infant compared to an adult? a. higher percentage of body fat b. higher volumes of sinus discharge c. relatively smaller head size d. tongue that is proportionally larger
D Infant neck flexion causes acute airway obstruction. Although the head is larger, an infant's nasal passages are proportionately smaller than are an adult's. In addition, the infant's jaw is much rounder and the tongue is much larger relative to the size of the oral cavity. These anatomic differences increase the likelihood of airway obstruction when an infant becomes unconscious and loses muscle tone. DIF: Application REF: p. 162
79. What does the detection of lymphatic channels on standard chest radiographs indicate? a. abnormally low pressures in the lymphatic channels b. anastomoses with the pulmonary circulation c. normal fibrotic changes that occur with aging d. system that is overwhelmed by excessive fluid
D Lymphatic channels are usually not visible on chest radiographs. They may be detected if they are distended or thickened by disease. The "butterfly" pattern that radiates from the hilar region of both lungs during acute development of pulmonary edema is thought to largely be the result of interstitial and lymph vessel distension with fluid. In this situation, the lymphatic drainage system has been overwhelmed by a sudden and excessive surge of fluid from the circulation. The development of a pleural effusion is also evidence that the lymphatic system is unable to remove excess fluid in the lung. DIF: Application REF: p. 179
110. What can the release of histamine and other chemical mediators from the mast cells in the airways cause? 1. bronchoconstriction 2. bronchodilation 3. vasoconstriction 4. vasodilation a. 2 and 4 b. 1 and 3 c. 2 and 3 d. 1 and 4
D Mast cells are also found in the submucosa and release numerous and potent vasoactive and bronchoactive substances such as histamine. Histamine causes vasodilation and bronchoconstriction, acting directly on smooth muscle. DIF: Application REF: p. 192
131. If premature delivery is anticipated, all of the following will help determine lung maturity, except: a. the presence of oligohydramnios b. ecithin-sphingomyelin (L:S) ratio c. phosphatidylglycerol (PG) concentration d. body mass index (BMI)
D Quantification of these phospholipids (the L/S ratio and PG concentration) provides a predictive index of the lung maturity in the fetus before birth and the risks of the development of respiratory distress.14 For example, an L/S ratio of 2 or more indicates a relatively low risk for the development of respiratory distress syndrome while an L/S ratio of less than 1.5 is associated with a high risk. Conditions that lead to reduced fetal breathing and amniotic fluid formation (oligohydramnios) are linked to incomplete inflation of the lung with fluid and poorly developed (hypoplastic) lungs. DIF: Application REF: p. 153
122. Why is pulmonary surfactant such an important biologic substance? a. It clears out cellular debris. b. It is an alveolar macrophage. c. It promotes lung contraction aiding exhalation. d. It promotes lung stability.
D Surfactant functions to reduce the surface tension of the alveolus, which results in shedding water from the alveolar surface; helps to prevent alveolar surface tensiondriven collapse; improves lung compliance; and reduces the work of breathing. DIF: Application REF: p. 198
98. Three folds of tissue between the posterior base of the tongue and the epiglottis form a small space that is a key landmark in oral intubation. What is this called? a. false vocal cords b. palatine fold c. taurus tubularus d. vallecula
D The base of the tongue is attached to the epiglottis by three folds. These folds form a space between the tongue and the epiglottis called the vallecula, which is a key landmark in oral intubation (Figure 8-36). DIF: Recall REF: p. 186
97. What is the leaf-shaped cartilage that extends from the base of the tongue and is attached by ligaments to the thyroid cartilage? a. arytenoid cartilage b. cricoid cartilage c. cuneiform cartilage d. Epiglottis
D The cartilaginous and leaf-shaped epiglottis lies within and is attached to the thyroid cartilage by a flexible joint. DIF: Recall REF: p. 185
39. What external landmark can be used to show the highest point the dome of the right hemidiaphragm reaches in a healthy individual? a. fifth rib posteriorly b. sixth rib posteriorly c. seventh rib posteriorly d. eighth rib posteriorly
D The highest portion of the right dome sits at the eighth or ninth thoracic vertebra posteriorly and at the fifth rib anteriorly. DIF: Recall REF: p. 166
23. Approximately how many alveoli are there in a 10-year-old's lung? a. 50 million b. 200 million c. 350 million d. 500 million
D The human lung continues to develop alveoli for years until it reaches a stable stage where the total number have increased to about 480 million alveoli. All of the development is complete by 10 years of age. DIF: Recall REF: p. 160
78. Which of the following statements are true of the pulmonary lymphatic system? 1. It consists of both superficial and deep vessels. 2. It drains into the right lymphatic or thoracic duct. 3. Vessels begin as dead-end lymphatic channels in the lung. 4. With phagocytes, it defends against foreign material. a. 1, 3, and 4 b. 2, 3, and 4 c. 2 only d. 1, 2, 3, and 4
D The lymphatic system plays an important role in the specific defenses of the immune system. It removes bacteria, foreign material, and cell debris via the lymph fluid and through the action of various phagocytic cells (e.g., macrophages) that provide defense against foreign material and cells that are able to penetrate deep into the lung. It also produces a variety of lymphocytes and plasma cells to aid in defense. Both roles are essential for maintaining normal function of the respiratory system. Most of the pulmonary lymphatic system consists of superficial and deep vessels. The superficial (pleural) vessels that drain the lung surface and pleural space are more numerous over the lower half of the upright lung. Both drain the blind lymphatic capillaries in the respective regions. The deeper lymph vessels are closely associated with the small airways but do not extend into the walls of the alveolar-capillary membranes. Lymph fluid is collected by the loosely formed lymphatic capillaries and drains through the lymph vessels toward the hilum. The lymph fluid rejoins the general circulation after passing through the right lymphatic or thoracic duct, which drains into the jugular, subclavian, and/or innominate veins. The lymph fluid then mixes with blood and returns to the right heart. DIF: Application REF: p. 179
59. What is the mediastinum? a. membranous sac surrounding the heart and great vessels b. middle layer of muscle fibers constituting the heart c. point of division of the trachea into the bronchi d. structure separating the right and left thoracic cavities
D The mediastinum lies between the left and right pleural cavities that contain the lungs (Figure 8-16). DIF: Recall REF: p. 173
55. To what structures do the parietal pleural membranes adhere or cover? a. fissures b. intrapulmonary bronchi c. lung d. mediastinum
D The parietal pleural membrane lines the chest wall and mediastinum, while the lungs are covered by the visceral pleura. DIF: Recall REF: p. 173
91. The subdivisions of the pharynx include which of the following? 1. nasopharynx 2. oropharynx 3. laryngopharynx a. 2 and 3 b. 1 and 2 c. 1 and 3 d. 1, 2, and 3
D The pharynx is subdivided into the nasopharynx, oropharynx, and hypopharynx or laryngopharynx. DIF: Recall REF: p. 185
68. The pulmonary venous circulation does which of the following? 1. delivers oxygenated blood back to the heart 2. delivers unoxygenated blood to the lungs 3. empties into the left atrium 4. empties into the right atrium a. 2 and 3 b. 1 and 4 c. 2 and 4 d. 1 and 3
D The pulmonary venous system drains the capillary beds that have received oxygen from the alveoli and delivers the oxygenated blood into the left atrium. DIF: Application REF: p. 175
105. Why do most aspirated |ects and fluids end up in the right mainstem bronchus instead of the left mainstem bronchus? a. The left bronchus is more in line with the trachea. b. The left bronchus is shorter than the right. c. The right bronchus is larger than the left. d. The right bronchus is more in line with the trachea.
D The right bronchus branches off from the trachea at an angle of about 20 to 30 degrees, and the left bronchus branches with an angle of about 45 to 55 degrees (Figure 8-44). The right bronchus's lower angle of branching results in a greater frequency of foreign body passage into the right lung because of the more direct pathway. DIF: Application REF: p. 187
56. What is the function of the very small amount of pleural fluid that is found in the pleural space? a. composes part of anatomic shunt b. liquid barrier for pathogens c. part of pulmonary blood flow d. reduces friction
D The small volume of pleural fluid is spread out over the entire surface of both lungs and functions as a lubricant to reduce friction as the lungs move within the thorax and as an airtight seal that adheres together the two pleural membranes. DIF: Application REF: p. 173
129. Which of following are the embryonic germinal tissue layers form all tissues and organs? 1. endoderm 2. mesoderm 3. ectoderm 4. rectoderm a. 2 only b. 2 and 3 c. 1, 2, and 4 d. 1, 2, and 3
D The three embryologically distinct germinal tissue layers form all tissues and organs: endoderm, mesoderm, and ectoderm. DIF: Recall REF: p. 148
95. What is the cartilage that is commonly referred to as the Adam's apple? a. arytenoid b. cricoid c. cuneiform d. thyroid
D The thyroid cartilage forms most of the upper portion of the larynx and is generally referred to as the Adam's apple. DIF: Recall REF: p. 185
66. Fluid transport to and from the lungs is provided by which of the following? 1. bronchial circulation 2. lymphatic system 3. pulmonary circulation a. 2 and 3 b. 1 and 3 c. 2 only d. 1, 2, and 3
D The vascular supply of the lungs is composed of the pulmonary and bronchial circulations. The pulmonary circulation carries mixed venous blood from the systemic circuit to the lungs to increase oxygen and reduce carbon dioxide content of blood. The bronchial circulation provides systemic arterial blood to the airways and pleura to support their metabolic needs. A network of lymphatics is also involved in fluid transport from the lungs. The lymphatic system removes fluid from the lung tissue and pleural space and returns it to the systemic circulation. DIF: Application REF: p. 175
3. By what mechanism does gas exchange across the lung occur? a. active transport b. facilitated diffusion c. facilitated transport d. simple diffusion
D This close "match" of gas and blood across a large but extremely thin blood-gas barrier membrane enables efficient gas exchange to occur by simple diffusion. DIF: Application REF: p. 148
2. What is meant by "internal respiration"? a. any gas exchange that occurs inside the body b. consumption of oxygen in the mitochondria c. continuous absorption of oxygen and excretion of carbon dioxide d. exchange of gases between the blood and the tissue
D This process supports internal respiration, which is the exchange of gases between blood and tissues. DIF: Application REF: p. 148
64. What is the primary mechanism that stops the lungs from collapsing at the end of exhalation? a. Radial tethers, stretched to their maximum length, then halt lung collapse. b. Surfactant neutralizes the tendency of the lung to collapse. c. There is a tendency of the chest wall to lock at the level of FRC. d. There is an equal opposing tendency of the chest wall to expand.
D This tendency of the lung to collapse is counteracted by the thoracic wall's tendency to spring outward and to hold the lung inflated. DIF: Application REF: p. 175
86. What are the three bony projections that arise from the lateral walls of the nasal cavity that enhance filtration and humidification? a. alar nasi b. frontal sinuses c. palatine tonsils d. turbinates
D Three shelf-like bones protrude into the cavity from the lateral walls. These bony shelves are called the superior, middle, and inferior concha or turbinates. The concha function to increase the surface area of the nasal cavity, which enhances filtration and humidification. DIF: Application REF: p. 182
101. What could the "effort closure" of the larynx facilitate? a. crying b. talking c. whispering d. yelling
D Tight closure of the larynx and the buildup of intrapulmonary pressure through muscular effort is called effort closure. Effort closure of the larynx is necessary for generating loud sounds and for effective coughing and sneezing. DIF: Application REF: p. 187
84. What may happen if the irritant receptors in the lung are stimulated? 1. bronchoconstriction 2. reflex closure of the glottis 3. reflex slowing of the heart (bradycardia) a. 2 and 3 b. 1 and 3 c. 2 only d. 1, 2, and 3
D When the irritant receptors are stimulated, it can result in bronchoconstriction, hyperpnea, glottic closure, cough, and sneeze. Stimulation of these receptors can also cause a reflex slowing of the heart rate (bradycardia). DIF: Application REF: p. 181
102. What position is used to open the airway in an unconscious patient? a. neck extension b. neck flexion c. recovery position d. sniff position
D With loss of consciousness, the head flexes forward, which can partially or completely obstruct the upper airway. (Figure 8-41, A). Extension of the head and lower jaw into the "sniff" position alleviates this obstruction (Figure 8-41, C). Extension of the head moves the tongue away from the rear of the pharynx. This technique is used to maintain the airway in unconscious patients and facilitates placement of artificial airways. DIF: Application REF: p. 187
