Deck 1: Digestion, Absorption, Transport, and Excretion of Nutrients

Question 1

After surgical removal of a large portion of the small intestine, what functional complication is most likely to develop?

A)Changes in dietary habits
B)Impaired digestion
C)Loss of absorptive tissue
D)Elimination of dietary residue

Answer 1

C
The small intestine is the primary site of nutrient absorption because of its large absorption surface area.Secretions from the liver, gallbladder, and pancreas can still contribute to digestion of intestinal contents.However, decreased absorption of nutrients and food components may result in more intestinal remains and residue.A patient may change dietary habits as a result of gastrointestinal discomfort experienced after intestinal resection, but this is not a functional complication.

Question 2

Pepsinogen is converted to pepsin when it comes in contact with

A)enterokinase.
B)trypsinogen.
C)hydrochloric acid.
D)peptidases.

Answer 2

C
Pepsinogen is secreted in the stomach and converted to its active form by the acid environment of the stomach.Enterokinase is secreted by the brush border of the small intestine in response to presence of chyme.Trypsinogen is secreted by the pancreas and activated by enterokinase.Various peptidases are secreted by either brush border or the pancreas.

Question 3

Which of the following is formed by bacterial synthesis in the colon?

A)Vitamin K
B)Vitamin D
C)Vitamin B6
D)Niacin

Answer 3

A
Colonic bacteria produce vitamin K, vitamin B₁₂, thiamin, and riboflavin.Vitamin D may be metabolized by exposure of precursor vitamin D in the skin to ultraviolet light.The human body can synthesize niacin from the amino acid tryptophan.Vitamin B₆ must be obtained from dietary sources such as meats, whole grains, vegetables, and nuts.

Question 4

If a patient experiences malabsorption of fat resulting from an impaired ability to produce adequate bile salts for micelle formation, how may fat absorption be improved?

A)By increasing short-chain fatty acids in the diet
B)By increasing medium-chain fatty acids in the diet
C)By increasing long-chain fatty acids in the diet
D)By restricting dietary intake of cholesterol

Question 5

Which of the following is an advantage to using medium-chain triglycerides when fat malabsorption occurs?

A)MCTs pass directly into the portal vein without esterification.
B)MCTs pass directly into the lymphatic system without esterification.
C)MCTs transport long-chain triglycerides through the lymph.
D)MCTs pass through the lymphatic system undigested.

Question 6

How often do the cells lining the intestinal tract recycle?

A)Every 2 to 3 days
B)Every 3 to 5 days
C)Every 5 to 7 days
D)Every 10 to 14 days

Question 7

Which of the following is a list of enzymes released from the pancreas?

A)Insulin, trypsin, and secretin
B)Lactase, isomaltase, and dextrinase
C)Protease, pepsin, and gastrin
D)Trypsin, chymotrypsin, and carboxypeptidase

Question 8

What is the function of enterogastrone?

A)Inhibits carbohydrate digestion
B)Enhances carbohydrate digestion
C)Enhances protein digestion
D)Inhibits gastric secretion and motility

Question 9

What effect may be achieved by eating a diet high in prebiotic carbohydrates?

A)Decreased SCFA production in the bowel
B)Increased growth of Lactobacilli spp.
C)Decreased absorption of bile salts
D)Increased absorption of cation minerals

Question 10

Which intestinal hormone is released in the presence of fat and glucose and results in delayed gastric emptying and satiety?

A)Glucose-dependent insulinotropic peptide (GIP)
B)Cholecystokinin (CCK)
C)Gastrin
D)Pancreatic lipase

Question 11

Absorption occurs in the stomach for which of the following nutrients?

A)Vitamins
B)Carbohydrates
C)Minerals
D)Alcohol

Question 12

Which of the following bacterial genuses tend to occur the most frequently in the adult colon?

A)Bacteroides
B)Escherichia
C)Lactobacilli
D)Helicobacter

Question 13

How long does it take for small intestine contents to reach the ileocecal valve?

A)18 to 72 hours
B)3 to 8 hours
C)1 to 2 hours
D)2 to 3 hours

Question 14

What happens to cellulose and lignin as they go through the GI tract?

A)They are converted into glucose before absorption.
B)They are converted into glucose and absorbed by active transport.
C)They are excreted in the feces unchanged.
D)They are excreted in the feces as glucose.

Question 15

Which is the process by which minerals are absorbed when they are bound to an acid, organic acid, or amino acid?

A)Cotransportation
B)Carrier protein
C)Competitive inhibition
D)Chelation

Question 16

What are primarily absorbed by the large intestine?

A)Water and fats
B)Carbohydrates
C)Proteins
D)Water and electrolytes

Question 17

What is the function of secretin?

A)Stimulation of gastric secretions and increased motility
B)Stimulation of gallbladder contraction and the release of bile
C)Stimulation of the pancreas to secrete water and bicarbonate
D)Stimulation of the parietal cells to secrete gastrin

Question 18

By which transport mechanism are most vitamins absorbed from the small intestine into the blood?

A)Passive diffusion
B)Active diffusion
C)Facilitative diffusion
D)Passive osmosis

Question 19

The sight or smell of food produces vagal stimulation of the parietal cells of the gastric mucosa, resulting in the increased production of what?

A)Motilin
B)Hydrochloric acid
C)Cholecystokinin
D)Secretin

Question 20

In what form is dietary fat absorbed from the lumen of the intestine?

A)Chylomicron
B)Micelle
C)Triglyceride
D)Lipoprotein