45 terms

Chapter 25

____ is the physiological process that moves a nutrient from the outside to the inside of the body
The serous membranes that suspend the stomach and intestines from the abdominal wall are called
These nutrients are all absorbed without being digested except
These are all accessory organs of the digestive system except
Each of the following lists some of the tissue layers of the digestive tract. Which one has them in the correct order from lumen to external surface?
lamina propia, muscularis mucosae, subucosa, muscularis externa, serosa
The small intestine is suspended from the abdominal wall by
the mesentery
Chemical digestion breaks down ___ into ____
nucleic acids; nucleotides
The surface of the tongue is covered with ____ stratified squamous epithelium and has bumps called ______ site of taste buds
nonkeratinized; lingual papillae
Infants have _____ deciduous teeth, whereas adults have _______ permanent teeth
From superficial to deep, these are the structures found in a typical tooth
These are normally found in saliva except
The ______ gland is an extrinsic salivary gland, whereas the ______ gland is an intrinsic salivary gland
submandibular; lingual
The swallowing center is located in
the medulla oblongata
The buccal phase of swallowing is under ______ control and the pharyngo-esophageal phase is _______.
central nervous system; controlled by autonomicreflexes
Acid reflux into the esophagus(heartburn) is normally prevented by
the lower esophageal sphincter (LES)
Hydrochloric acid (HCI) is secreted by _____ cells
______, which is secreted by ______ cells, is necessary for Vitamin B12 absorption
intrinsic factor; parietal
Pepsinogen is produced by ______ and is activated by ______
chief cells; hydrochloric acid (HCI) secreted by parietal cells
Why are several digestive enzymes secreted as zymogens
so they act only in the stomach lumen and do not digest intracellular proteins
The enterogastric reflex serves to
inhibit gastric motility when there is chyme in the small intestine
_____ is a hormone, whereas _______ is an enzyme
secretin; pepsin
_____ is associated with food stretching the stomach and activating myenteric and vagovagal reflexes, which in turn stimulate gastric secretions
the gastric phase
The organ that stores excess glucose and releases it later into the blood is
the liver
A hepatic (portal) triad consists of
bile ductule, branch of the hepatic artery and branch of hepatic portal vein
Of the following components of bile, only _____ has/have a digestive function
bile salts
The ____ synthesizes bile acids by metabolizing _____
liver; cholestrol
Pancreatic enzymes are secreted in response to the hormone
cholecytokinin (CCK)
Which of these is not a component of the pancreatic juice?
Which of these nutrients is absorbed by the lacteals of the small intestine?
Which of the following enzymes functions at the lowest pH
Which of these is the site of contact digestion
brush border of the small intestine
The small intestine has a very large absorptive surface associated with all these structures except
The migrating motor complex
milks the chyme toward the colon
The _____ of the small intestine is/are similar to the ______ of the stomach
intestional crypts; gastric pits
Carbohydrate digestion begins in the ____, whereas protein digestion begins in the
mouth; stomach
The sodium-glucose transport protein(SGLP)
transports glucose and sodium from the intestinal lumen into the epithelial cells
Amino acids and monosaccharides are absorbed in the _____ and fatty acids are absorbed in the ______
small intestine; small intestine too
Lecithin prepares fats for hydrolysis by forming
emulsification droplets
Proteins are digested by different enzymes acting in the following sequence
pepsin, trypsin, carboxypeptidase, dipeptidase
_____ transport lipids to the surface of the intestinal absorptive cells, which process them into ______
micelles; chylomicrons
The three most abundant classes of nutrients are
fats, proteins, and carbohydrates
The muscle tone of the _____ along the colon contracts it lengthwise, causing its walls to bulge and form pouches called ______.
taeniae coli; haustra
Bacterial flora carry out all of the following except
digest most of the proteins we get in the diet
Bacteria constitute about _____ % of the dry weight of feces
Defecation is stimulated by
stretching of the rectum