Deck 22: The Respiratory System

Question 1

Tracheal obstruction is life threatening.

Answer 1

True

Question 2

The inflation (Hering-Breuer)reflex is a potentially dangerous response that may cause overinflation of the lung.

Answer 2

False

Question 3

The Heimlich maneuver is a procedure in which air in the lungs is used to expel a piece of food that obstructs the opening to the trachea.

Answer 3

True

Question 4

Changes in arterial pH can modify respiration rate and rhythm even when carbon dioxide and oxygen levels are normal.

Question 5

The average individual has 500 ml of residual volume in his lungs.

Question 6

The functions of the nasal conchae are to enhance the air turbulence in the cavity and to increase the mucosal surface area exposed to the air.

Question 7

Intrapleural pressure is normally about 4 mm Hg less than the pressure in the alveoli.

Question 8

Labored breathing is termed dyspnea.

Question 9

The largest amount of carbon dioxide is transported in the bloodstream in the form of carbonic anhydrase.

Question 10

The paired lungs occupy the mediastinum of the thoracic cavity.

Question 11

The lungs are perfused by two circulations: the pulmonary and the bronchial.The pulmonary circulation is for oxygenation of blood.The bronchial circulation supplies blood to the lung structures (tissue).

Question 12

The alveolar ventilation rate is the best index of effective ventilation.

Question 13

Atelectasis (lung collapse)renders the lung useless for ventilation.

Question 14

Smoking diminishes ciliary action and eventually destroys the cilia.

Question 15

Strong emotions and pain,acting through the limbic system and hypothalamus,send signals to the respiratory centers that modulate respiratory rate and depth.

Question 16

Increased temperature results in decreased O₂ unloading from hemoglobin.

Question 17

During normal quiet breathing,approximately 750 ml of air moves into and out of the lungs with each breath.

Question 18

The parietal pleura lines the thoracic wall.

Question 19

In chronic bronchitis,mucus production is decreased and this leads to the inflammation and fibrosis of the mucosal lining of the bronchial tree.

Question 20

The olfactory mucosal lining of the nasal cavity contains the receptors for the sense of smell.

Question 21

Under certain conditions,the vocal folds act as a sphincter that prevents air passage.

Question 22

Which of the following is the leading cause of cancer death for both men and women in North America?

A)lung
B)colorectal
C)esophageal
D)skin

Question 23

Which of the following is true regarding normal quiet expiration of air?

A)It depends on the complete lack of surface tension on the alveolar wall.
B)It is a passive process that depends on the recoil of elastic fibers that were stretched during inspiration.
C)It requires contraction of abdominal wall muscles.
D)It is driven by increased blood CO2 levels.

Question 24

Dalton's law of partial pressures states that the total pressure exerted by a mixture of gases is the sum of the pressures exerted independently by each gas in the mixture.

Question 25

Oxygenated hemoglobin releases oxygen more readily when the pH is more basic.

Question 26

As carbon dioxide enters systemic blood,it causes more oxygen to dissociate from hemoglobin (the Haldane effect),which in turn allows more CO₂ to combine with hemoglobin and more bicarbonate ions to be generated (the Bohr effect).

Question 27

The statement,"in a mixture of gases,the total pressure is the sum of the individual partial pressures of gases in the mixture" paraphrases ________.

A)Charles' law
B)Henry's law
C)Boyle's law
D)Dalton's law

Question 28

The local matching of blood flow with ventilation is ________.

A)ventilation-perfusion coupling
B)the Bohr effect
C)the Haldane effect
D)chloride shifting

Question 29

With the Bohr effect,more oxygen is released because a(n)________.

A)decrease in pH (acidosis)weakens the hemoglobin-oxygen bond
B)increase in pH (alkalosis)strengthens the hemoglobin-oxygen bond
C)decrease in pH (acidosis)strengthens the hemoglobin-oxygen bond
D)increase in pH (alkalosis)weakens the hemoglobin-oxygen bond

Question 30

Surfactant helps to prevent the alveoli from collapsing by ________.

A)humidifying the air before it enters
B)protecting the surface of alveoli from dehydration and other environmental variations
C)warming the air before it enters
D)interfering with the cohesiveness of water molecules,thereby reducing the surface tension of alveolar fluid

Question 31

The main site of gas exchange is the ________.

A)alveolar duct
B)respiratory bronchiole
C)alveoli
D)alveolar sacs

Question 32

The walls of the alveoli are composed of two types of cells,type I and type II alveolar cells.The function of type II alveolar cells is to ________.

A)replace mucus in the alveoli
B)protect the lungs from bacterial invasion
C)trap dust and other debris
D)secrete surfactant

Question 33

Which of the following maintains the patency (openness)of the trachea?

A)pseudostratified ciliated epithelium
B)C-shaped cartilage rings
C)surfactant production
D)surface tension of water

Question 34

In the plasma,the quantity of oxygen in solution is ________.

A)only about 1.5% of the oxygen carried in blood
B)not present except where it is combined with carrier molecules
C)about equal to the oxygen combined with hemoglobin
D)greater than the oxygen combined with hemoglobin

Question 35

For gas exchange to be efficient,the respiratory membrane must be ________.

A)between 5 and 6 micrometers thick
B)at least 3 micrometers thick
C)0)5 to 1 micrometer thick
D)The thickness of the respiratory membrane is not important in the efficiency of gas exchange.

Question 36

Complete the following statement using the choices below.Air moves out of the lungs when the pressure inside the lungs is ________.

A)equal to the pressure in the atmosphere
B)less than the pressure in the atmosphere
C)greater than the intra-alveolar pressure
D)greater than the pressure in the atmosphere

Question 37

The relationship between gas pressure and gas volume is described by ________.

A)Dalton's law
B)Charles' law
C)Boyle's law
D)Henry's law

Question 38

Intrapulmonary pressure is the ________.

A)difference between atmospheric pressure and respiratory pressure
B)pressure within the pleural cavity
C)pressure within the alveoli of the lungs
D)negative pressure in the intrapleural space

Question 39

The loudness of a person's voice depends on the ________.

A)length of the vocal folds
B)force with which air rushes across the vocal folds
C)thickness of vestibular folds
D)strength of the intrinsic laryngeal muscles

Question 40

Nasal conchae mainly work on inhalation to warm and moisten air.They serve minor functions for exhalation.

Question 41

Which of the choices below describes the forces that act to pull the lungs away from the thorax wall and thus collapse the lungs?

A)compliance and transpulmonary pressures
B)compliance and the surface tension of the alveolar fluid
C)the natural tendency for the lungs to recoil and the surface tension of the alveolar fluid
D)the natural tendency for the lungs to recoil and transpulmonary pressures

Question 42

Which respiratory-associated muscles would contract or relax during forced expiration,for example blowing up a balloon?

A)external intercostals would contract and diaphragm would relax
B)internal intercostals and abdominal muscles would contract
C)diaphragm contracts,internal intercostals would relax
D)diaphragm would contract,external intercostals would relax

Question 43

Which of the choices below is NOT a role of the pleurae?

A)allow the lungs to easily glide easily over the thorax wall during breathing movements
B)assist in blood flow to and from the heart because the heart sits between the lungs
C)help limit the spread of local infections
D)help divide the thoracic cavity into three chambers

Question 44

Which of the following is correct regarding acclimatization?

A)At high altitudes,hemoglobin's affinity for O2 is increased because BPG concentrations increase.
B)High-altitude conditions always result in lower-than-normal hemoglobin saturation levels because less O2 is available to be loaded.
C)Decreases in arterial PO2 cause the peripheral chemoreceptors to become less responsive to increases in PCO2.
D)When blood O2 levels decline,the kidneys produce more erythropoietin,which stimulates breakdown of red blood cells in the spleen.

Question 45

How is the bulk of carbon dioxide transported in blood?

A)as carbonic acid in the plasma
B)as bicarbonate ions in plasma after first entering the red blood cells
C)chemically combined with the heme portion of hemoglobin
D)chemically combined with the amino acids of hemoglobin as carbaminohemoglobin in the red blood cells

Question 46

Which statement about CO2 is FALSE?

A)More CO2 dissolves in the blood plasma than is carried in the RBCs.
B)Its concentration in the blood is decreased by hyperventilation.
C)CO2 concentrations are greater in venous blood than arterial blood.
D)Its accumulation in the blood is associated with a decrease in pH.

Question 47

Which of the following counteracts the movement of bicarbonate ions from the RBC?

A)the Bohr effect
B)the Haldane effect
C)release of hydrogen ion
D)chloride shifting

Question 48

Select the correct statement about the pharynx.

A)The pharyngeal tonsil is located in the laryngopharynx.
B)The palatine tonsils are embedded in the lateral walls of the nasopharynx.
C)The laryngopharynx blends posteriorly into the nasopharynx.
D)The pharyngotympanic (auditory)tube drains into the nasopharynx.

Question 49

The amount of air that can be inspired above the tidal volume is called ________.

A)inspiratory reserve volume
B)vital capacity
C)reserve air
D)expiratory capacity

Question 50

Tidal volume is air ________.

A)exchanged during normal breathing
B)remaining in the lungs after forced expiration
C)inhaled after normal inspiration
D)forcibly expelled after normal expiration

Question 51

Which of the following INCORRECTLY describes mechanisms of CO2 transport?

A)as bicarbonate ions in plasma
B)7-10% of CO2 is dissolved directly into the plasma
C)just over 20% of CO2 is carried in the form of carbaminohemoglobin
D)attached to the heme part of hemoglobin

Question 52

The lung volume that represents the total volume of exchangeable air is the ________.

A)tidal volume
B)expiratory reserve volume
C)inspiratory capacity
D)vital capacity

Question 53

Which of the following is NOT a stimulus for breathing?

A)rising blood pressure
B)arterial PO2 below 60 mm Hg
C)acidosis resulting from CO2 retention
D)rising carbon dioxide levels

Question 54

Possible causes of hypoxia include ________.

A)too little oxygen in the atmosphere
B)getting very cold
C)obstruction of the esophagus
D)taking several rapid deep breaths

Question 55

Which of the following is NOT a form of lung cancer?

A)squamous cell carcinoma
B)Kaposi's sarcoma
C)small cell carcinoma
D)adenocarcinoma

Question 56

Which of the following determines lung compliance?

A)muscles of inspiration
B)alveolar surface tension
C)airway opening
D)flexibility of the thoracic cage

Question 57

Oxygen and carbon dioxide are exchanged in the lungs and through all cell membranes by ________.

A)active transport
B)filtration
C)diffusion
D)osmosis

Question 58

The larynx contains ________.

A)lateral cartilage ridges called false vocal folds
B)the thyroid cartilage
C)an upper pair of avascular mucosal folds called true vocal folds
D)a cricoid cartilage also called the Adam's apple

Question 59

Which of the following refers to the movement of air into and out of the lungs?

A)pulmonary ventilation
B)external respiration
C)internal respiration
D)gas exchange

Question 60

The major nonelastic source of resistance to air flow in the respiratory passageways is ________.

A)air pressure
B)friction
C)surfactant
D)surface tension

Question 61

The nose serves all of the following functions EXCEPT ________.

A)cleansing the air
B)warming and humidifying the air
C)as a passageway for air movement
D)as the direct initiator of the cough reflex

Question 62

Which of the choices below is NOT a factor that promotes oxygen binding to and dissociation from hemoglobin?

A)number of red blood cells
B)temperature
C)partial pressure of oxygen
D)partial pressure of carbon dioxide

Question 63

Spirometry results reveal a vital capacity of two liters which is well below the predicted value of five liters.This suggests which disorder?

A)emphysema
B)asthma
C)restrictive disease
D)obstructive pulmonary disease

Question 64

Which of the disorders below is characterized by destruction of the walls of the alveoli producing abnormally large air spaces that remain filled with air during exhalation?

A)coryza
B)tuberculosis
C)pneumonia
D)emphysema

Question 65

Which of the following is an appropriate response to carbon monoxide (CO)poisoning?

A)hyperventilation to exhale CO from the body
B)hyperbaric oxygen chamber to increase PO2 and clear CO from the body
C)slow breathing into a paper bag
D)immediate application of bicarbonate ions to facilitate removal of CO from Hb

Question 66

Select the correct statement about oxygen transport in blood.

A)During conditions of acidosis,hemoglobin is able to carry oxygen more efficiently.
B)Increased BPG levels in the red blood cells enhance oxygen-carrying capacity.
C)A 50% oxygen saturation level of blood returning to the lungs might indicate an activity level higher than normal.
D)During normal activity,a molecule of hemoglobin returning to the lungs carries one molecule of O2.

Question 67

Factors that influence the rate and depth of breathing include ________.

A)stretch receptors in the alveoli
B)temperature of alveolar air
C)voluntary cortical control
D)thalamic control

Question 68

Select the correct statement about the physical factors influencing pulmonary ventilation.

A)Surfactant helps increase alveolar surface tension.
B)A lung that is less elastic will require less muscle action to perform adequate ventilation.
C)A decrease in compliance causes an increase in ventilation.
D)As alveolar surface tension increases,additional muscle action will be required.

Question 69

The respiratory membrane is a combination of ________.

A)respiratory bronchioles and alveolar ducts
B)alveolar and capillary walls and their fused basement membranes
C)respiratory bronchioles and alveolar sacs
D)atria and alveolar sacs

Question 70

Most inspired particles such as dust fail to reach the lungs because of the ________.

A)action of the epiglottis
B)ciliated mucous lining in the nose
C)porous structure of turbinate bones
D)abundant blood supply to nasal mucosa

Question 71

Which of the following does NOT influence hemoglobin saturation?

A)BPG
B)nitric oxide
C)temperature
D)partial pressure of carbon dioxide

Question 72

Which of the following is responsible for holding the lungs to the thorax wall are ________.

A)the visceral pleurae and the changing volume of the lungs
B)the smooth muscles of the lung
C)the diaphragm and the intercostal muscles alone
D)surface tension from pleural fluid and negative pressure in the pleural cavity

Question 73

Inspiratory capacity is ________.

A)air inspired after a tidal inhalation
B)functional residual capacity
C)the total amount of exchangeable air
D)the total amount of air that can be inspired after a tidal expiration

Question 74

According to the oxygen-hemoglobin dissociation curve,PO2 in the lungs of 100 mm Hg results in Hb being 98% saturated.At high altitude,there is less O2.At a PO2 in the lungs of 80 mm Hg,Hb would be ________ saturated.

A)98%
B)less than 50%
C)100%
D)95%

Question 75

Which of the following is INCORRECT?

A)The amount of gas flowing in and out of the alveoli is directly proportional to the difference in pressure or pressure gradient between the external atmosphere and the alveoli.
B)Resistance equals pressure gradient over gas flow.
C)Pressure gradient equals gas flow over resistance.
D)Gas flow equals pressure gradient over resistance.

Question 76

The symptoms of hyperventilation may be averted by breathing into a paper bag because it ________.

A)reduces brain perfusion by constricting cerebral blood vessels
B)helps retain oxygen in the blood
C)lowers blood pH levels
D)helps retain carbon dioxide in the blood

Question 77

The erythrocyte (red blood cell)count increases after a while when an individual goes from a low to a high altitude because the ________.

A)basal metabolic rate is higher at high altitudes
B)concentration of oxygen and/or total atmospheric pressure is lower at high altitudes
C)concentration of oxygen and/or total atmospheric pressure is higher at higher altitudes
D)temperature is lower at higher altitudes

Question 78

Select the correct statement about the neural mechanisms of respiratory control.

A)The pons is thought to be instrumental in the smooth transition from inspiration to expiration.
B)The dorsal respiratory group neurons depolarize in a rhythmic way to establish the pattern of breathing.
C)The ventral respiratory group is contained within the pons.
D)The pontine respirator group (PRG)continuously stimulates the medulla to provide inspiratory drive.

Question 79

Which center is located in the pons?

A)inspiratory center
B)pacemaker neuron center
C)pontine respirator group (PRG)
D)expiratory center

Question 80

For inspiration of air,which of the following happens first?

A)diaphragm descends and rib cage rises
B)intrapulmonary pressure drops
C)air (gases)flows into lungs
D)thoracic cavity volume decreases