Mcq Pathophysiology.docx

Considering the sequence of structures through which air enters the pulmonary system, the pharynx is to the trachea as the: a. bronchioles are to the segmental bronchi. b. alveoli are to the alveolar ducts. c. alveolar ducts are to the respiratory bronchioles. d. respiratory bronchioles are to the alveolar ducts. e. All of the above are correct. The dorsal respiratory group (DRG) of neurons: a. sets the automatic rhythm of respiration. b. modifies the rhythm of respiration. c. is active when increased ventilation is required. d. None of the above is correct.

Stretch receptors: a. are sensitive to volume changes in the lung. b. are located in airway smooth muscles. c. decrease ventilatory rate when stimulated. d. prevent lung overinflation when stimulated. e. All of the above are correct.

The respiratory unit consists of: a. cilia. b. bronchiolar arteries and veins. c. goblet cells and alveoli. d. respiratory bronchioles and alveoli. e. All of the above are correct.

Oxygen diffusion from the alveolus to the alveolar-capillary occurs because: a. the Pao2 is less in the capillary than in the alveolus. b. the Pao2 is greater in the atmosphere than in the arterial blood. c. oxygen diffuses faster than CO2. d. the Pao2 is higher in the capillary than in the alveolus. The cilia of the bronchial wall: a. ingest bacteria. b. trigger the sneeze reflex. c. trap and remove bacteria. d. propel mucus and trapped bacteria toward the oropharynx. e. Both a and c are correct. When the diaphragm and external intercostal contract: a. the intrathoracic volume increases. b. the intrathoracic pressure increases. c. the intrathoracic volume decreases. d. None of the above is correct.

Surfactant: a. facilitates O2 exchange. b. produces nutrients for the alveoli. c. permits air exchange between alveolar ducts. d. facilitates alveolar expansion during inspiration. e. All of the above are correct.

A shift to the right in the oxyhemoglobin dissociation curve: a. prevents oxygen release at the cellular level. b. causes oxygen to bind more tightly to hemoglobin. c. improves oxygen release and increases oxygen movement into the cells. d. Both a and b are correct

The left bronchus: a. is shorter and wider than the right. b. is symmetrical with the right. c. has a course more vertical than that on the right. d. is more angled than the right. e. has more bronchial wall layers than the right.

Beginning at the lumen of the tube, the sequence of layers of the gastrointestinal tract is: a. mucosa, submucosa, muscularis, serosa. b. submucosa, mucosa, serosa, muscularis. c. submucosa, mucosa, muscularis, skeletal muscle. d. serosa, muscularis, mucosa, submucosa. Pepsinogen: a. must be activated by HCl. b. is secreted by the chief cells. c. is a precursor to pepsin. d. All of the above are correct.

The nervous pathway involved in salivary secretion requires stimulation of: a. receptors in the taste buds and somatic motor impulses to the salivary glands. b. receptors in the mouth, sensory impulses, and parasympathetic impulses to the salivary glands. c. taste receptors, sensory impulses, and somatic motor impulses to the salivary glands. d. pressoreceptors in blood vessels and autonomic impulses to the salivary glands. The digestive functions performed by the saliva and salivary amylase, respectively, are: a. moistening and protein digestion. b. deglutition and fat digestion. c. peristalsis and polysaccharide digestion. d. lubrication and carbohydrate digestion.

During nervous control of gastric secretion, the gastric glands secrete before food enters the stomach. This stimulus to the glands comes from: a. gastrin. b. impulses over somatic nerves from the hypothalamus. c. motor impulses from the cerebral cortex and cerebellum. d. parasympathetic impulses over the vagus nerve.

The secretion of gastric juice: a. occurs only when swallowed food comes in contact with the stomach. b. is entirely under the control of the hormone gastrin. c. is entirely under the control of the hormone enterogastrone. d. is stimulated by the presence of saliva in the stomach. e. occurs in three phases: cephalic, gastric, and intestinal.

Food would pass rapidly from the stomach into the duodenum if it were not for the: a. fundus. b. epiglottis. c. rugae. d. cardiac sphincter. e. pyloric sphincter.

The muscularis of the gastrointestinal tract is: a. skeletal muscle throughout the tract, particularly in the esophagus and large intestine. b. the layer that contains the blood capillaries for the entire wall of the tract. c. composed principally of keratinized epithelium. d. composed of circular fibers and longitudinal fibers.

Normally, when chyme leaves the stomach: a. the nutrients are ready for absorption into the blood. b. the amount of inorganic salts has been increased by the action of hydrochloric acid. c. its pH is neutral. d. the proteins have been partly digested into polypeptides.

Which layer of the small intestine includes microvilli? a. submucosa b. mucosa c. muscularis d. serosa

Which is not an example of mechanical digestion? a. chewing b. churning and mixing of food in the stomach c. peristalsis and mastication d. conversion of protein molecules into amino acids

The chief role played by the pancreas in digestion is to: a. secrete insulin and glucagon. b. churn the food and bring it into contact with digestive enzymes. c. secrete enzymes, which digest food in the small intestine. d. assist in absorbing digested foods.

he absorptive fate of the end products of digestion may be summarized by which of the following? a. Most fatty acids are absorbed into the blood; glucose and amino acids are absorbed into the lymphatic system. b. Amino acids and monosaccharides are absorbed into blood capillaries; most fatty acids are

absorbed into lymph. c. Amino acids and fatty acids are absorbed into lymph capillaries; glycerol and glucose are absorbed into blood capillaries. d. Fatty acids are absorbed into blood capillaries; glycerol, glucose, and amino acids are absorbed into lymph.

Pancreatic juice is to trypsin as gastric juice is to: a. salivary amylase. b. pepsin. c. mucin. d. intrinsic factor.

The pancreas: a. lies mostly on the left side of the abdominal cavity, anterior to the stomach and the spleen. b. secretes all of its products directly into the bloodstream. c. is a gland with its duct ultimately opening into the duodenum. d. contains cells with an endocrine function for the determination of secondary sex characteristics. e. is classified as a digestive exocrine gland and does not have endocrine functions. An obstruction of the common bile duct would cause blockage of bile coming from: a. the gallbladder. b. the liver but not from the gallbladder. c. both the liver and the gallbladder. d. the pancreatic duct but not from the gallbladder.

The chief role played by the pancreas in digestion is to: a. secrete insulin and glucagon. b. churn the food and bring it into contact with digestive enzymes.

c. secrete enzymes, which digest food in the small intestine. d. assist in absorbing the digested foods.

A lobule of the liver contains a centrally located: a. vein with radiating hepatocytes and sinusoids. b. arteriole with radiating capillaries and Kupffer cells. c. hepatic sinus with radiating sinusoids. d. hepatic duct with radiating Kupffer cells and cords of hepatic cells.

The human adult liver does not: a. store glycogen. b. produce erythrocytes. c. convert ammonia to urea. d. produce blood coagulation proteins. One function of the somatic nervous system that is not performed by the autonomic nervous system is conduction of impulses: a. to involuntary muscles and glands. b. to the central nervous system. c. to skeletal muscles. d. between the brain and spinal cord. There is one-way conduction at a synapse because: a. only postsynaptic neurons contain synaptic vesicles. b. acetylcholine prevents nerve impulses from traveling in both directions. c. only the presynaptic neuron contains neurotransmitters.

d. only dendrites release neurotransmitters.

The composition of cerebrospinal fluid is: a. the same as blood. b. distilled H2O with dissolved salts. c. a plasma-like liquid with glucose, salts, and proteins. d. a heavy mucous solution with dissolved salts, glucose, and urea.

An autonomic ganglion can be described as: a. the site of synapses between visceral efferent neurons. b. a site where spinal reflexes occur. c. a point of synapse between parasympathetic and sympathetic neurons. d. the place where unconscious sensations occur.

The sympathetic division of the autonomic nervous system: a. mobilizes energy in times of need. b. is innervated by cell bodies from T1 through L2. c. is innervated by cell bodies located in the cranial nerve nuclei. d. Both a and b are correct. e. Both a and c are correct.

The parasympathetic division of the autonomic nervous system: a. conserves and stores energy. b. has relatively short postganglionic neurons. c. Both a and b are correct.

d. has paravertebral ganglia.