Deck 3: Digestion,Absorption,and Metabolism

Question 1

If the speed of peristalsis were to increase,the result would be

A) heartburn.
B) vomiting.
C) diarrhea.
D) constipation.

Answer 1

C
If peristalsis were to speed up,food would move quickly through the gastrointestinal tract,and time for absorption of nutrients and water would be insufficient,which would result in diarrhea.Constipation can be related to decreased peristalsis.Heartburn is caused by reflux of stomach contents in the esophagus and is not related to peristalsis.Vomiting is caused by a reverse in the direction of peristalsis.

Question 2

The part of the digestive system that is easiest to live without is the

A) taste buds.
B) gallbladder.
C) large intestine.
D) appendix.

Answer 2

D
The least vital part of the intestine is the appendix;it does not have any known function in humans.The taste buds are important for the enjoyment of food and to stimulate food intake.The gall bladder is not essential,but it allows for storage of bile to be released as needed for optimal digestion.The large intestine is important for absorption of water and a few other nutrients;it is possible to live without it,but intake must be adapted to compensate for unabsorbed fluid,electrolytes,and other substances.

Question 3

The body process over which people have most conscious control is

A) ingestion.
B) digestion.
C) metabolism.
D) excretion.

Answer 3

A
People can choose the foods and fluids they ingest.Digestion,metabolism,and excretion are largely automatic processes.A person's actions may affect those processes indirectly (e.g.,exercise affects metabolism,stress may affect digestion),but people have less control over them than over ingestion.

Question 4

If the large intestine did not carry out its main function,feces would be

A) alkaline.
B) acidic.
C) liquid.
D) very dry.

Question 5

An example of a problem caused by a sphincter muscle not operating properly is

A) constipation.
B) gallbladder disease.
C) heartburn.
D) peptic ulcer.

Question 6

If pancreatic secretions were absent,

A) there would be no bicarbonate to buffer the acid in chyme entering the duodenum.
B) mechanical digestion in the stomach would be inhibited.
C) the hormone secretin would not be secreted by the small intestine.
D) the gallbladder would not contract to release bile into the small intestine.

Question 7

When someone walks by a bakery and smells the fresh bread,his or her mouth starts to water.As the person thinks about eating the fresh bread,another digestive function that starts to occur is

A) peristalsis in the small intestine.
B) stimulation of pancreatic secretions.
C) increased blood flow to the gut and liver.
D) release of the hormone gastrin in the stomach.

Question 8

The most important function of the villi of the small intestine is to

A) increase the secretion of enzymes for digestion.
B) increase the surface area for absorption of nutrients.
C) excrete waste into the intestines.
D) secrete hormones in response to nutrients in the gut.

Question 9

Nutrients are considered to have become part of the body only once they have

A) been placed inside the mouth.
B) been swallowed.
C) passed through the microvilli cells.
D) been stored throughout the body.

Question 10

The best description of an enzyme is a(n)

A) chemical messenger.
B) acid and alkali buffer.
C) emulsifier.
D) organic catalyst.

Question 11

Examples of mechanical digestion include

A) activity of salivary amylase in the mouth.
B) churning and mixing of food in the stomach.
C) action of bile breaking fats into smaller droplets.
D) effects of secretin in stimulating the pancreas to release bicarbonate.

Question 12

The most important functions of the small intestine are

A) digestion and denaturation.
B) segmentation and excretion.
C) digestion and absorption.
D) peristalsis and mechanical digestion.

Question 13

What is the main difference between passive diffusion and active transport?

A) In active transport,the villi membrane surrounds the substance.
B) Active transport requires energy;passive diffusion does not.
C) Passive diffusion is involuntary;active transport is voluntary.
D) Active transport requires enzymes;passive diffusion does not.

Question 14

Peristalsis is necessary to make it possible for people to _____ food.

A) chew
B) digest
C) swallow
D) smell and taste

Question 15

Most mechanical breakdown of food occurs in the

A) large intestine.
B) liver and pancreas.
C) mouth and stomach.
D) esophagus and mouth.

Question 16

Chemicals that act as messengers are called

A) proteins.
B) hormones.
C) enzymes.
D) nerve impulses.

Question 17

Release of digestive secretions into the small intestine is caused by _____ that are released when _____.

A) enzymes;food enters the stomach
B) enzymes;food enters the small intestine
C) hormones;food enters the stomach
D) hormones;enters the small intestine

Question 18

The layer of the gastrointestinal tract that contributes most to mechanical digestion of food is the

A) mucosa.
B) submucosa.
C) muscularis.
D) serosa.

Question 19

People tend to feel full for longer after eating a high-fat meal rather than a low-fat meal because

A) ingestion of fat causes release of hormones that signal a feeling of fullness to the brain.
B) food stays in the stomach for longer to allow emulsification by bile and digestion by gastric enzymes.
C) fat in the duodenum causes release of gastric inhibitory polypeptide,which decreases peristalsis of the stomach.
D) metabolism of the products of fat metabolism by the liver takes longer than metabolism of other nutrients.

Question 20

The action of salivary amylase in the mouth is an example of

A) chemical digestion.
B) chewing.
C) mechanical digestion.
D) peristalsis and segmentation.

Question 21

A person who complains of problems with gas,bloating,and diarrhea if he or she eats breakfast cereal with milk,but not if he or she eats pancakes or waffles,may have

A) milk allergy.
B) gluten intolerance.
C) irritable bowel syndrome.
D) lactose intolerance.

Question 22

Dehydration may occur after

A) vomiting and diarrhea.
B) constipation and heartburn.
C) esophagitis and anemia.
D) gastroesophageal reflux and hiatal hernia.

Question 23

The bloodstream carries nutrients to the liver soon after absorption because the liver

A) produces hormones that regulate blood glucose level.
B) is an important site of metabolism and production of vital substances.
C) is able to determine which substances should be stored and eliminated.
D) has functions similar to those of the stomach in relation to the digestive process.

Question 24

A busy and stressed person who eats very few fruits and vegetables and does not take time to exercise is likely to experience

A) vomiting.
B) diarrhea.
C) constipation.
D) lactose intolerance.

Question 25

If peristalsis were to reverse direction,the result would be

A) vomiting.
B) diarrhea.
C) constipation.
D) intestinal failure.

Question 26

The adjectives mechanical and chemical describe two

A) actions needed to cook food.
B) ways to move substances in the body.
C) types of action that result in digestion.
D) ways in which molecules are transported into and out of cells.

Question 27

Healing of a broken bone is an example of

A) anabolism.
B) catabolism.
C) absorption.
D) metabolism.

Question 28

If a meal is eaten at noon,by 8 PM that evening,the food would probably be in the

A) stomach.
B) small intestine.
C) large intestine.
D) colon.

Question 29

An example of catabolism is the

A) building of new muscle tissue during growth.
B) breakdown of glucose to provide energy.
C) synthesis of protein from amino acids.
D) use of enzymes to digest protein and release amino acids.

Question 30

If the small intestine did not release secretin,the result would be that

A) the stomach would not release gastric juices to moisten and begin digestion of swallowed food.
B) the gallbladder would not release bile to help the process of fat breakdown.
C) peristalsis would slow down,and food would move very slowly through the intestines.
D) the chyme entering the small intestine would be too acidic for digestive enzymes to work.