Chapter 15 - The Digestion and Absorption of Food
The gall bladder A) Synthesizes bile B) Stores bile C) Is stimulated to contract by the hormone secretin D) Synthesizes CCK
B
water-soluble, liver
LDL, __ __ Lipoprotein, is a type of lipoprotein particle found in the __, which transport __ and cholesterol to tissues.
___ are enzymes that break down fats like triglycerides, whereas bile salts emulsify fats.
Lipases
__, not chylomicrons, are smaller fat droplets produced by the action of __ and bile salts on fat droplets.
Micelles, lipases
The luminal surface of intestinal epithelial cells is covered with small projections called A) Villi B) Microvilli C) Lacteals D) Mucosa
Microvilli
Which of the following statements is NOT correct? A) Constipation is caused by decreased motility in the large intestines B) Diarrhea may result from decreased fluid absorption in the large intestines C) A high intake of dietary fiber reduces the risk of constipation because it increases distension and motility in the large intestines This is the correct answer. D) Bacterial diarrhea results from a bacterial toxin that blocks water channels in the cells of the large intestines
Most forms of bacterial diarrhea do not directly interfere with water movement into or out of the cells of the intestines
Which of the following is NOT secreted by cells within gastric glands? A) Pepsinogen B) Gastrin C) HCl D) Secretin E) Intrinsic factor
Secretin
Salivation in response to the smell of food would not occur if there was a malfunction in the ______ phase of gastrointestinal control. A) Cephalic B) Gastric C) Intestinal D) Colon
The cephalic phase
Which of the following pairs of digestive actions correctly describes two of the functions of the large intestine? A) Bicarbonate secretion and bacterial action B) Acid secretion and bacterial action This is the correct answer. C) Water reabsorption and mass movements D) Mixing action and intestinal hormone production E) Migrating myoelectric complexes and amino acid absorption
The colon or large intestine works on the waste products of digestion by transporting sodium from the lumen to the blood with the accompanying osmotic absorption of water.
lipoprotein, epithelial
The hepatic portal vein is the route of transport of __ nutrients to the __.
During swallowing, food enters the stomach by passing through the A) Pyloric sphincter B) Ileocecal sphincter C) Epiglottis D) Lower esophageal sphincter
The lower esophageal sphincter
On a daily basis, a greater volume of material enters the lumen of the gastrointestinal tract from the body than is ingested as food and water.
True.
dissolve, lowers, pH, pepsin, protein
Trypsin and __ are both enzymes of the __ intestine which function in __ digestion
Which of the following substances is transported across the intestinal epithelial cells by means of a special protein called the "intrinsic factor"? A) Amino acids B) Sodium C) Glucose D) Vitamin B-12
Vitamin B-12
Bile salts provide __, emulsifying agents, which associate with the exterior of the __ lipid droplets, leaving the polar portions of the amphipathic molecules __ at the water surface. They then repel other __ droplets and thus prevent __ to large fat droplets.
amphipathic, nonpolar, exposed, lipid, re-aggregation,
Amylase breaks __ down to short-branched chains of glucose molecules called __.
polysaccharides, oligosaccharides
The function of the enzyme enterokinase is to A) Stimulate bicarbonate secretion by the pancreas B) Stimulate secretion of gastrin by the stomach This is the correct answer. C) Convert trypsinogen into trypsin D) Convert pepsinogen into pepsin E) Cleave dipeptides into amino acids
proteolytic enzyme that splits off a peptide from pancreatic trypsinogen to form the active enzyme trypsin.
Exits via __ to __, MAJOR site of nutrient absorption and has 3 parts, __. __ digestive enzyme from __ empty into __ furthering digestion, __ pass from lumen to __ and __.
pyloric sphincter, small intestine, duodenum, jejunum, ileum. Liver, pancreas, duodenum, nutrients, blood, lymph
Stomach ___ fold expands, __, __, __ secreted, muscle churned and mix bolus into ___.
rugae, HCl, pepsinogen and regulatory hormones, chyme
Food in the mouth is masticated, oral cavity secrete
saliva to moist food and begins digestion, swallowed,
Carbohydrate and starch digestion begins in the mouth with the action of the
salivary enzyme amylase.
More complete digestion of polysaccharides to disaccharides and monosaccharides takes place in the
small intestine by the action of pancreatic amylase AND enzymes on the __ __ of the __ intestine.
__ blocks upper pharynx so food don't go into nasal cavity,
soft palate
Chylomicrons do not enter intestinal capillaries but rather enter
the small blind lymph vessels called lacteals, which join the cardiovascular system near the heart.
Tunneling food mass, now ___ through ___ to stomach via wave-like involuntary muscle contractions called ___.
bolus, esophagus, peristalsis
Which of the following have been implicated as the most frequent and important cause of peptic (gastric) ulcers in humans? A) Increased activity of the autonomic nervous system in persons with chronic stress This is the correct answer. B) Infection of the stomach wall by Helicobacter pylori (a type of bacteria) C) Consuming high levels of dairy products and hot, spicy foods D) Increased production of hydrochloric acid (HCl) or gastrin by the stomach
cause stomach ulcers in humans is infection of the stomach wall by the H. pylori bacteria.
Within __ glands parietal cells secrete __ and __ __, chief cells secrete __, and __ cells secrete __.
endocrine, gastric, HCl, intrinsic factor, enteroendocrine, pepsinogen, gastrin
In the absence of bile salts, fat digestion would be
impaired but not prevented.
Secretin also __ the activity of the __. However, another duodenal hormone, __, is responsible for stimulating __ contraction.
inhibits, stomach, CCK (cholecystokinin), gallbladder
__ are projections of the membrane of __ __ __.
intestinal epithelial cells
The __ hormone CCK, aka __, secretion from intestinal __ into the __ on the arrival of the __ meal particles in the __ __, to __ for __ contraction.
intestinal, cholecystokinin, epithelium, blood, fatty, small intestine, signal, gallbladder
Chyme not absorbed enters __ and passed the __ and __, __, __, __ colon. __ and __ are absorbed while chyme converts to __ and stored in __ until nervous defecation __ to exit the __.
large intestine, cecum and ascending, transverse, descending, sigmoid colon. Water and salts, feces, rectum, reflex, anal canal
Bile is synthesized by the __ cells and is released into the __ __ __, which lead out of the __ to the __.
liver, small bile ducts, liver, gallbladder
Final __ digestion of __ occurs in the small intestine as a result of enzymatic __ of __ to __.
luminal, carbohydrates, hydrolysis, oligosaccharides, monosaccharides
Amylase digests starch to the disaccharide __ and to short __ __ of __. The final digestion to __ is achieved by __ located on the brush border of the small intestine.
maltose, branching chains, glucose, monosaccharides, enzymes
It is the ___ that are actively transported across the intestinal epithelial cells, not disaccharides.
monosaccharides
The __ is composed of the epithelial layer with its __ __ and the __ __. Projections of the mucosa into the __ are called __. Lacteals are __ __ found within each __ (singular of villi).
mucosa, lamina propria, muscularis mucosa, lumen, villi. lymphatic vessels, villus.
Which of the following is NOT an enzyme used for protein digestion? A) Pepsin B) Trypsin C) HCl D) Chymotrypsin
HCl is not an enzyme.
The average person consumes about __ ml of water and __ grams of food but an additional __ ml of fluid, containing many different __ and __, comes from __ glands as well as the glands of the __ __ __ and __.
1200, 800, 7000, proteins, electrolytes, salivary, stomach, pancreas, liver, and intestines.
The emulsification of fats A) Results in the formation of small fat droplets B) Depends upon the polar structure of bile salts C) Results in the formation of chylomicrons D) Depends upon the polar structure of bile salts
A; The emulsification of fats is the disruption of large fat droplets into smaller droplets.
The liver produces _______ which aids in the digestion of _______. A) Amylase; starch B) Pepsin, proteins C) Hydrochloric acid; proteins D) Bile; lipids
Bile, which aids in the digestion of lipids by emulsifying large lipid droplets into smaller lipid droplets.
Which of the following statements about the transport of the absorbed products of fat digestion is true?
C) Triglycerides are transported through the __ as part of lipoproteins called chylomicrons
Which of the following statements regarding digestion and absorption of carbohydrates is true?
D) Final luminal digestion of carbohydrates produces monosaccharides.
__ bile is secreted by the __ and shunted into the __ where it becomes __ and is __ until __.
Dilute, liver, gallbladder, concentrated, stored, needed
Which of the following statements regarding lipid digestion and absorption is true?
E) The products of lipid digestion are resynthesized into triglycerides in intestinal epithelial cells
facial voluntary muscle neck tongue contract pushing food through pharynx. ___ blocks food into the respiratory system.
Epiglottis
Which of the following statements concerning stomach HCl production is NOT correct? A) Increasing acidity in the stomach stimulates endocrine cells in the gastric epithelium to produce somatostatin that inhibits further HCl secretion This is the correct answer. B) HCl production increases in response to carbohydrates entering the stomach C) HCl secretion is inhibited when acidity increases in the small intestine D) Gastrin, histamine, and acetylcholine all act to increase HCl secretion
HCl production is stimulated in response to the presence of proteins and peptides, not carbohydrates
Gallstones are crystals composed of This is the correct answer. A) Cholesterol B) Phospholipids C) Billirubin D) Bicarbonate
In most cases gallstones are crystals of cholesterol
Acid secretion in the stomach is carried out by the ____________ cells of the stomach glands. These cells contain an enzyme called ________________. The function of this enzyme is to catalyze the reaction between ______________ and water. A) Chief; acetylcholine-esterase; carbon dioxide B) Parietal; amylase; bicarbonate C) Parietal; carbonic anhydrase; carbon dioxide D) Mucus; carbonic anhydrase; bicarbonate E) Enteroendocrine; gastrin; pepsinogen
Parietal; carbonic anhydrase; carbon dioxide.
Proteins are completely digested to produce individual amino acids which is the only way they can be absorbed into epithelial cells.
This statement is false.
T/F Fat soluble vitamins are absorbed in the small intestine by diffusion or mediated transport whereas water soluble vitamins are absorbed in a similar way as fats are absorbed, through emulsification and enzymatic digestion.
This statement is false.
T/F The duodenal hormone secretin decreases gastric motility and acid production but increases pancreatic bicarbonate release as well as contraction of gallbladder.
This statement is false.
The absorption of iron into the blood is enhanced when epithelial cells of the small intestine increase their synthesis of the iron-binding protein ferritin.
This statement is false.
The actions of salivary and pancreatic amylases digest starches to produce many copies of the monosaccharide glucose.
This statement is false.
The products of lipid digestion diffuse into the intestinal epithelium as micelles.
This statement is false.
The secretion of gastrin by endocrine cells in the stomach lining is stimulated by increasing gastric acidity.
This statement is false.
T/F Hormonal and neural regulation of the digestive system affects two functions: smooth muscle activity and secretory activity.
This statement is true.
The onset of gastric peristaltic contractions is independent of input from the enteric or autonomic nervous system or hormones.
This statement is true.
___ are resynthesized in the epithelial cells of the small intestine.
Triglycerides;