Chapter 22: Respiratory

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

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 expansion of respiratory muscles that were contracted during inspiration and the lack of surface tension on the alveolar wall B) the negative feedback of expansion fibers used during inspiration and the outward pull of surface tension due to surfactant C) combined amount of CO2 in the blood and air in the alveoli D) the recoil of elastic fibers that were stretched during inspiration and the inward pull of surface tension due to the film of alveolar fluid

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

The walls of the alveoli are composed of two types of cells, type I and type II. The function of type II is to ________. A) replace mucus in the alveoli B) trap dust and other debris C) protect the lungs from bacterial invasion D) secrete surfactant

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

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

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

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

The major nonelastic source of resistance to air flow in the respiratory passageways is ________. A) air pressure B) surfactant C) friction D) surface tension

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) action of the epiglottis D) porous structure of turbinate bones

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

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

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

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

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

Which of the following incorrectly describes mechanisms of CO2 transport? A) 7-10% of CO2 is dissolved directly into the plasma B) attached to the heme part of hemoglobin C) as bicarbonate ion in plasma D) 20% of CO2 is carried in the form of carbaminohemoglobin

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

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

The main site of gas exchange is the ________. A) respiratory bronchiole B) alveolar duct C) alveolar sacs D) alveoli

The loudness of a person's voice depends on the ________. A) strength of the intrinsic laryngeal muscles B) thickness of vestibular folds C) force with which air rushes across the vocal folds D) length of the vocal folds

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

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) 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) basal metabolic rate is higher at high altitudes

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

Which of the following does not influence hemoglobin saturation? A) BPG B) temperature C) carbon dioxide D) nitric oxide

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

Which of the following counteracts the movement of bicarbonate ions from the RBC? A) the Haldane effect B) release of hydrogen ion C) chloride shifting D) the Bohr effect

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

The relationship between gas pressure and gas volume is described by ________. A) Dalton's law B) Boyle's law C) Charles' law D) Henry's law

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

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

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

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

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

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

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 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) the natural tendency for the lungs to recoil and the surface tension of the alveolar fluid

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

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

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

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

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

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

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

Surfactant helps to prevent the alveoli from collapsing by ________. A) warming the air before it enters B) humidifying 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

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

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

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

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

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) Boyle's law C) Henry's law D) Dalton's law

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

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

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

The local matching of blood flow with ventilation is ________. A) ventilation-perfusion coupling B) the Bohr effect C) the Haldane effect D) chloride shifting

The factors 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) surface tension from pleural fluid and negative pressure in the pleural cavity D) the diaphragm and the intercostal muscles alone

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

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) emphysema D) pneumonia

Complete the following statement using the choices below. Air moves out of the lungs when the pressure inside the lungs is ________. A) greater than the intra-alveolar pressure B) equal to the pressure in the atmosphere C) less than the pressure in the atmosphere D) greater than the pressure in the atmosphere

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