physiology exam 3

Which of the following pressure (mm Hg) would be recorded as intra-alveolar pressure during a normal resting inspiration? a. 756 b. 760 c. 764 d. 768 e. 0

a. 756

When intra-alveolar pressure becomes greater than atmospheric pressure, a. air will flow out of the lungs. b. air will flow into the lungs. c. there will be no air flow. d. both (a) and (b) above. e. none of these answers.

a. air will flow out of the lungs

Which of the following events occurs during expiration? a. diaphragm moves upward b. thoracic volume increases c. external intercostal muscles contract d. ribs are elevated e. phrenic nerve is inactive

a. diaphragm moves upward

Type I alveolar cells a. form the wall of the alveoli. b. secrete pulmonary surfactant. c. contract during expiration to force air out of the alveoli. d. two of these answers. e. all of these answers.

a. form the walls of the alveoli

A transmural pressure gradient exists across the lung wall because the ____ pressure is less than the ____ pressure. a. intrapleural, intra-alveolar. b. intra-alveolar, intrapleural. c. intrapleural, atmospheric. d. atmospheric, intra-alveolar. e. none of these answers.

a. intrapleural, intra-alveolar

Which skeletal muscle serves as an accessory respiratory muscle? a. rectus abdominus. b. diaphragm. c. external intercostal. d. internal intercostal. e. none of the above

a. rectus abdominus

Which of the following is not a function of the respiratory system? a. transports O2 to the tissues b. contributes to maintenance of normal acid-base balance c. provides a route for heat and water elimination d. enables speech, singing, and other vocalization e. removes, modifies, activates, or inactivates various materials passing through the pulmonary circulation

a. transports oxygen to the tissues

Which activity below is not a respiratory event? a. carbon dioxide is exchanged in the alveoli. b. cells produce nitrogen by their metabolism. c. gas exchange between tissues and the blood. d. oxygen is exchanged in the alveoli. e. pulmonary ventilation.

b. cells produce nitrogen by their metabolism

Bronchodilation of the air passages involves the ____ of their smooth muscle contraction and the ____ of their radius. a. decrease, decrease. b. decrease, increase. c. increase, decrease. d. increase, increase.

b. decrease, increase

The inspiratory muscles include the a. diaphragm and internal intercostal muscles. b. diaphragm and external intercostal muscles. c. diaphragm and abdominal muscles. d. internal and external intercostal muscles. e. none of these answers.

b. diaphragm and external intercostal muscle

Which of the following does not bring about increased airway resistance? a. asthma. b. epinephrine. c. slow-reactive substance of anaphylaxis. d. emphysema. e. excess mucus production.

b. epinephrine

​The entire sequence of events involved in the exchange of O2 and CO2 between the body cells and the environment is known as a. internal respiration. b. external respiration. c. ventilation. d. breathing. e. both ventilation and breathing are correct.

b. external respiration

Which of the following structures serves as a common passageway for both the respiratory and digestive systems? a. nose b. pharynx c. trachea d. bronchi e. esophagus

b. pharynx

Which factor would result in bronchoconstriction? a. sympathetic stimulation. b. secretion of acetylcholine c. epinephrine secretion. d. increased carbon dioxide concentration. e. none of these answers.

b. secretion of acetylcholine

When blood flow to an area of the lungs is reduced but the area receives normal air flow all of the following occur except a. the concentration of CO2 in this area will be decreased. b. the change in CO2 concentration will cause the smooth muscles of the local airways to relax. c. the change in CO2 concentration will lead to increased resistance of local airways. d. the change in O2 concentration will lead to dilation of local blood vessels. e. the change in O2 concentration will lead to decreased vascular resistance.

b. the change in CO2 concentration will cause the smooth muscles of the local airways to relax.

Which of the following pressure (mm Hg) would be recorded as intrapleural pressure during a normal resting expiration? a. 752 b. 756 c. 760 d. 764 e. 0

c. 760

During which of the following would the intrapleural pressure be greater than atmospheric pressure? a. forced inspiration. b. passive expiration. c. forced expiration. d. pneumothorax. e. none of these answers.

c. forced expiration

At the end of a normal expiration when outward air flow has ceased, a. intra-alveolar pressure is less than atmospheric pressure. b. intra-alveolar pressure is greater than atmospheric pressure. c. intra-alveolar pressure is equal to atmospheric pressure. d. intrapleural pressure is greater than atmospheric pressure. e. intrapleural pressure is greater than intra-alveolar pressure.

c. intra-alveolar pressure is equal to atmospheric pressure.

Which of the following statements concerning pulmonary surfactant is incorrect? a. pulmonary surfactant is secreted by Type II alveolar cells. b. pulmonary surfactant is deficient in newborn respiratory distress syndrome. c. pulmonary surfactant promotes elastic recoil of the lungs. d. the cohesive force between a water molecule and an adjacent pulmonary surfactant molecule is much lower than the cohesive force between two adjacent water molecules. e. pulmonary surfactant reduces surface tension.

c. pulmonary surfactant promotes elastic recoil of the lungs.

The lungs contain: a. mostly smooth muscle b. only cartilage c. no elastic tissue d. about 500 million alveoli e. none of the above

d. about 500 million alveoli

The intrapulmonary pressure a. is the pressure within the air sacs of the lung. b. always equilibrates with atmospheric pressure. c. is always less than intrapleural pressure. d. both (a) and (b) above. e. all of these answers.

d. both (a) and (b) above

When the diaphragm contracts a. the volume of the thoracic cavity increases. b. lung volume increases as the lungs are forced to expand. c. the intra-alveolar pressure increases. d. both (a) and (b) above. e. all of these answers.

d. both (a) and (b) above

Which of the following promotes elastic recoil of the lungs? a. elastic fibers in the lung. b. surface tension of the fluid lining the alveoli. c. pulmonary surfactant. d. both (a) and (b) above. e. all of these answers.

d. both (a) and (b) above

During inspiration, a. intra-alveolar pressure falls below atmospheric pressure. b. the diaphragm contracts. c. the internal intercostal muscles contract. d. both (a) and (b) above. e. all of these answers.

d. both (a) and (b) above.

Airway resistance a. is normally the primary factor determining the amount of flow into/out of the lungs. b. is increased when the diameter of the airways becomes reduced. c. when elevated requires an increased pressure gradient between the lungs and atmosphere through vigorous respiratory efforts to move even normal volumes of air into and out of the lungs. d. both (b) and (c) above. e. all of these answers.

d. both (b) and (c) above.

Normal expirations are brought on by a. contraction of the external intercostals. b. contraction of the internal intercostals. c. contraction of the diaphragm. d. elastic recoil of inspiratory muscles. e. elastic recoil of expiratory muscles.

d. elastic recoil of inspiratory muscles.

COPD: a. affects inspiration to a greater degree than expiration b. forces small airways to stay open during expiration c. is the same as apnea d. increases airway resistance e. makes inspiration easier

d. increases airway resistance

Which of the following does not occur during expiration when a person is breathing quietly? a. the size of the thoracic cavity is reduced. b. the intra-alveolar pressure becomes greater than atmospheric pressure. c. air flows out of the lungs. d. the expiratory muscles contract. e. intrapleural pressure is less than intra-alveolar pressure.

d. the expiratory muscles contract

Which of the following is the last step that produces an inspiration? a. the atmospheric pressure becomes lower than the intrapleural pressure. b. the diaphragm contracts. c. the intercostal muscles contract. d. the intra-alveolar pressure becomes lower than the atmospheric pressure. e. the intrapleural pressure becomes positive.

d. the intra-alveolar pressure becomes lower than the atmospheric pressure

During forceful expirations a. the accessory expiratory muscles contract. b. the internal intercostals contract. c. the abdominal muscles contract. d. the ribs are brought closer together. e. all of these answers.

e. all of these answers

In addition to gas exchange the respiratory system plays a key role in a. enhancing venous return. b. water and temperature balance. c. body defense. d. both (a) and (c) above. e. all of these answers.

e. all of these answers

The lungs are held against the thoracic wall due to a. the negative intrapleural pressure. b. the positive intrapulmonary pressure. c. cohesiveness of the pleural fluids. d. both (a) and (c) above. e. all of these answers.

e. all of these answers

When the level of blood flow is not ideally matched with the amount of airflow in a localized area of lung tissue a. autoregulatory mechanisms are invoked. b. the autonomic nervous system couples the events more ideally. c. if airflow is low and blood flow to high, arteriolar vasoconstriction occurs. d. both (a) and (b) above. e. both (a) and (c) above.

e. both (a) and (c) above

Inspiratory events occur because a. the air pressure in the alveoli is greater than that of the atmosphere. b. the air pressure in the alveoli is less than that of the atmosphere. c. the volume of the thoracic cavity increases. d. both (a) and (c) above. e. both (b) and (c) above

e. both (b) and (c) above

Which of the following makes breathing more difficult? a. increased pulmonary compliance. b. increased airway resistance. c. decreased elastic recoil. d. both (a) and (b) above. e. both (b) and (c) above.

e. both (b) and (c) above