5) Unlike inspiration, expiration is a passive act because no muscular contractions are involved. Expiration, however, depends on two factors. Which of the choices below lists those two factors?
A) the recoil of elastic fibers that were stretched during inspiration and the inward pull of surface tension due to the film of alveolar fluid
B) the expansion of respiratory muscles that were contracted during inspiration and the lack of surface tension on the alveolar wall
C) the negative feedback of expansion fibers used during inspiration and the outward pull of surface tension due to surfactant
D) combined amount of CO2 in the blood and air in the alveoli

A

6) Which of the following maintains the patency (openness) of the trachea?
A) surface tension of water
B) surfactant
C) cartilage rings
D) pseudostratified ciliated epithelium

C

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

B

8) The relationship between the pressure and volume of gases is given by ________.
A) Boyle's law
B) Henry's law
C) Charles' law
D) Dalton's law

A

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

C

10) Surfactant helps to prevent the alveoli from collapsing by ________.
A) humidifying the air before it enters
B) warming the air before it enters
C) interfering with the cohesiveness of water molecules, thereby reducing the surface tension of alveolar fluid
D) protecting the surface of alveoli from dehydration and other environmental variations

C

11) For gas exchange to be efficient, the respiratory membrane must be ________.
A) at least 3 micrometers thick
B) 0.5 to 1 micrometer thick
C) between 5 and 6 micrometers thick
D) The thickness of the respiratory membrane is not important in the efficiency of gas exchange.

B

12) With the Bohr effect, more oxygen is released because a(n) ________.
A) decrease in pH (acidosis) strengthens the hemoglobin-oxygen bond
B) decrease in pH (acidosis) weakens the hemoglobin-oxygen bond
C) increase in pH (alkalosis) strengthens the hemoglobin-oxygen bond
D) increase in pH (alkalosis) weakens the hemoglobin-oxygen bond

B

13) The most powerful respiratory stimulus for breathing in a healthy person is ________.
A) loss of oxygen in tissues
B) increase of carbon dioxide
C) pH (acidosis)
D) pH (alkalosis)

B

14) Nerve impulses from ________ will result in inspiration.
A) the ventral respiratory group
B) the chemoreceptor center
C) Broca's center
D) the preoptic nucleus of the hypothalamus

A

15) In the plasma, the quantity of oxygen in solution is ________.
A) only about 1.5% of the oxygen carried in dissolved form
B) about equal to the oxygen combined with hemoglobin
C) greater than the oxygen combined with hemoglobin
D) not present except where it is combined with carrier molecules

A

16) Which of the following statements is incorrect?
A) During fetal life, lungs are filled with fluid.
B) Respiratory rate is lowest in newborn infants.
C) Descent of the diaphragm results in abdominal breathing.
D) The chest wall becomes more rigid with age.

B

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

A

18) Which of the following does not influence the increase in ventilation that occurs as exercise is initiated?
A) psychic stimuli
B) decrease in lactic acid levels
C) proprioceptors
D) simultaneous cortical motor activation of the skeletal muscles and respiratory center

B

19) Which of the following is not a form of lung cancer?
A) adenocarcinoma
B) Kaposi's sarcoma
C) small cell carcinoma
D) squamous cell carcinoma

B

20) Which of the following is not an event necessary to supply the body with O2 and dispose of CO2?
A) pulmonary ventilation
B) blood pH adjustment
C) internal respiration
D) external respiration

B

21) Which of the following is not true of the respiratory tract from the medium bronchi to the aveoli?
A) Cartilage gradually decreases and disappears at the bronchioles.
B) Resistance to air flow increases due to the increase in cross-sectional diameter.
C) Proportionally, smooth muscle decreases uniformly.
D) Lining of the tubes changes from ciliated columnar to simple squamous epithelium in the alveoli.

B

22) Which of the following determines lung compliance?
A) airway opening
B) flexibility of the thoracic cage
C) muscles of inspiration
D) alveolar surface tension

D

23) Tidal volume is air ________.
A) remaining in the lungs after forced expiration
B) exchanged during normal breathing
C) inhaled after normal inspiration
D) forcibly expelled after normal expiration

B

24) Which of the choices below determines the direction of respiratory gas movement?
A) solubility in water
B) partial pressure gradient
C) the temperature
D) molecular weight and size of the gas molecule

B

Possible causes of hypoxia include ________.
A) too little oxygen in the atmosphere
B) obstruction of the esophagus
C) taking several rapid deep breaths
D) getting very cold

A

The lung volume that represents the total volume of exchangeable air is the ________.
A) tidal volume
B) vital capacity
C) inspiratory capacity
D) expiratory reserve volume

B

Because the lungs are filled with fluid during fetal life, which of the following statements is true regarding respiratory exchange?
A) Respiratory exchanges are made through the ductus arteriosus.
B) Respiratory exchanges are not necessary.
C) Respiratory exchanges are made through the placenta.
D) Because the lungs develop later in gestation, fetuses do not need a mechanism for respiratory exchange.

C

Which of the following is not a stimulus for breathing?
A) rising carbon dioxide levels
B) rising blood pressure
C) arterial Po2 below 60 mm Hg
D) arterial pH resulting from CO2 retention

B

Respiratory control centers are located in the ________.
A) midbrain and medulla
B) medulla and pons
C) pons and midbrain
D) upper spinal cord and medulla

B

The amount of air that can be inspired above the tidal volume is called ________.
A) reserve air
B) expiratory reserve
C) inspiratory reserve
D) vital capacity

C

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

C

32) Oxygen and carbon dioxide are exchanged in the lungs and through all cell membranes by ________.
A) osmosis
B) diffusion
C) filtration
D) active transport

B

33) Select the correct statement about the pharynx.
A) The pharyngeal tonsil is located in the laryngopharynx.
B) The auditory tube drains into the nasopharynx.
C) The laryngopharynx blends posteriorly into the nasopharynx.
D) The palatine tonsils are embedded in the lateral walls of the nasopharynx.

B

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

A

35) Which respiratory-associated muscles would contract if you were to blow up a balloon?
A) diaphragm would contract, external intercostals would relax
B) internal intercostals and abdominal muscles would contract
C) external intercostals would contract and diaphragm would relax
D) diaphragm contracts, internal intercostals would relax

B

36) How is the bulk of carbon dioxide carried in blood?
A) chemically combined with the amino acids of hemoglobin as carbaminohemoglobin in the red blood cells
B) as the bicarbonate ion in the plasma after first entering the red blood cells
C) as carbonic acid in the plasma
D) chemically combined with the heme portion of hemoglobin

B

37) Which of the following is not found on the right lobe of the lung?
A) middle lobe
B) cardiac notch
C) horizontal fissure
D) oblique fissure

B

38) Which of the choices below is not a role of the pleura?
A) allows the lungs to inflate and deflate without friction
B) helps divide the thoracic cavity into three chambers
C) helps limit the spread of local infections
D) aids in blood flow to and from the heart because the heart sits between the lungs

D

40) Factors that influence the rate and depth of breathing include ________.
A) thalamic control
B) voluntary cortical control
C) stretch receptors in the alveoli
D) composition of alveolar air

B

41) Which of the following provide the greatest surface area for gas exchange?
A) alveolar sacs
B) alveoli
C) respiratory bronchioles
D) alveolar ducts

B

42) The respiratory membrane is a combination of ________.
A) respiratory bronchioles and alveolar ducts
B) alveolar and capillary walls and their fused basement membranes
C) atria and alveolar sacs
D) respiratory bronchioles and alveolar sacs

B

43) Gas emboli may occur because a ________.
A) person holds his breath too long
B) diver holds his breath upon ascent
C) pilot holds her breath upon descent
D) person breathes pure oxygen in a pressurized chamber

B

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

A

45) Which center is located in the pons?
A) pontine respirator group (PRG)
B) expiratory
C) inspiratory
D) pacemaker neuron center

A

46) The nose serves all the following functions except ________.
A) as a passageway for air movement
B) as the initiator of the cough reflex
C) warming and humidifying the air
D) cleansing the air

B

47) A premature baby usually has difficulty breathing. However, the respiratory system is developed enough for survival by ________.
A) 17 weeks
B) 24 weeks
C) 28 weeks
D) 36 weeks

C

47) Which of the following statements is true regarding the respiratory rate of a newborn?
A) The respiratory rate of a newborn is slow.
B) The respiratory rate of a newborn varies between male and female infants.
C) The respiratory rate of a newborn is approximately 30 respirations per minute.
D) The respiratory rate of a newborn is, at its highest rate, approximately 40-80 respirations per minute.

D

48) 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 pontine respirator group (PRG) continuously stimulates the medulla to provide inspiratory drive.
D) The ventral respiratory group is contained within the pons.

A

49) Which of the choices below is not a factor that promotes oxygen binding to and dissociation from hemoglobin?
A) partial pressure of oxygen
B) temperature
C) partial pressure of carbon dioxide
D) number of red blood cells

D

50) The factors responsible for holding the lungs to the thorax wall are ________.
A) the smooth muscles of the lung
B) the diaphragm and the intercostal muscles alone
C) the visceral pleurae and the changing volume of the lungs
D) surface tension from pleural fluid and negative pressure in the pleural cavity

D

52) The erythrocyte count increases after a while when an individual goes from a low to a high altitude because the ________.
A) temperature is lower at higher altitudes
B) basal metabolic rate is higher at high altitudes
C) concentration of oxygen and/or total atmospheric pressure is higher at higher altitudes
D) concentration of oxygen and/or total atmospheric pressure is lower at high altitudes

D

53) Most inspired particles such as dust fail to reach the lungs because of the ________.
A) ciliated mucous lining in the nose
B) abundant blood supply to nasal mucosa
C) porous structure of turbinate bones
D) action of the epiglottis

A

54) Which of the following is not possible?
A) Gas flow equals pressure gradient over resistance.
B) Pressure gradient equals gas flow over resistance.
C) Resistance equals pressure gradient over gas flow.
D) 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

55) Select the correct statement about the physical factors influencing pulmonary ventilation.
A) A decrease in compliance causes an increase in ventilation.
B) A lung that is less elastic will require less muscle action to perform adequate ventilation.
C) As alveolar surface tension increases, additional muscle action will be required.
D) Surfactant helps increase alveolar surface tension.

C

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

D

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

C