Chapter 38 - Structure and Function of the Digestive System Flashcards
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 particularly of keratinized epithelium.
d. composed of circular fibers and longitudinal fibers.
d. composed of circular fibers and longitudinal fibers
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 dissection
d. lubrication and carbohydrate digestion.
d. lubrication and carbohydrate digestion
The nervous pathway involved in salivary secretion requires the stimulation of:
a. receptors in the taste buds, impulses to the motor cortex, and somatic motor impulse to salivary glands.
b. receptors in the mouth, sensory impulses to a center in the brainstem, and parasympathetic impulses to salivary glands.
c. taste receptors, sensory impulses to centers in the brainstem, and somatic motor impulses to salivary glands.
d. pressoreceptors in the blood vessels, motor impulses, and autonomic impulses to salivary glands.
b. receptors in the mouth, sensory impulses to a center in the brainstem, and parasympathetic impulses to salivary glands
Food would pass rapidly from the stomach onto the duodenum if it were not for the :
a. fundus
b. epiglottis
c. rugae
d. cardiac sphincter
e. pyloric sphincter
e. pyloric sphincter
The secretion of gastric juice:
a. occurs when the stomach comes in contact with swallowed food.
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
e. occurs in three phases: cephalic, gastric, and intestinal
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.
d. parasympathetic impulse over the vagus nerve
Pepsinogen:
a. must be activated by HCl
b. is secreted by the chief cells
c. is important in the breakdown of proteins
d. All of the above are correct.
d. All of the above are correct
Beginning at the lumen, the sequence of layers of the gastrointestinal tract is:
a. mucosa, submucosa, muscularis, serosa
b. submucosa, mucosa, serous membrane, muscularis
c. submucosa, mucosa, muscularis, skeletal muscle
d. serous membrane, muscularis, mucosa, submucosa
a. mucosa, submucosa, muscularis, serosa
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
d. the proteins have been partly digested
Which layer of the small intestine includes microvilli?
a. sumucosa
b. mucosa
c. muscularis
d. serosa
b. mucosa
Which of the following 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
d. conversion of protein molecules into amino acids
Pancreatic juice is to trypsin as gastric juice is to:
a. salivary amylase
b. pepsin
c. mucin
d. intrinsic factor
b. pepsin
Which part of the small intestine is most distal from the pylorus?
a. jejunum
b. pyloric sphincter
c. duodenum
d. cardiac sphincter
e. common bile duct
a. jejunum
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 freely into the blood stream
c. is a slender flattened gland with its duct ultimately opening into the duodenum.
d. contains cells with endocrine function for the determination of secondary sex characteristics.
e. is classified as a digestive exocrine gland that does not have endocrine function.
c. is a slender flattened gland with its duct ultimately opening into the duodenum
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 that digest food in the small intestine.
d. assist in absorbing the digested food.
c. secrete enzymes that digest food in the small intestine
Among the structural features of the small intestine are villi, microvilli, and circular folds. Their function is to :
a. liberate hormones.
b. promote peristalsis.
c. liberate digestive enzymes
d. increase the surface area for absorption
d. increase the surface area for absorption