Chapter 41

Question 1

Animals that migrate great distances would obtain the greatest energetic benefit of storing chemical

Answer 1

fats

Question 2

To maintain adequate nutrition, animals require dietary access to certain amino acids. An amino acid that is referred to as “nonessential” would be best described as one that

Answer 2

can be made by the animal’s body from other substances.

Question 3

Which pair correctly associates a biochemical process with the appropriate mineral associated with its use in animals?

Answer 3

maintenance of bone and calcium

Question 4

Choose the list that presents the four stages of food processing in the order in which they naturally occur.

Answer 4

ingestion → digestion → absorption → elimination

Question 5

The gastrovascular cavity differs from the alimentary canal in that only the gastrovascular cavity _____.

Answer 5

has only a single opening

Question 6

Ingested dietary substances must cross cell membranes to be used by the body, a process known as

Answer 6

absorption

Question 7

An advantage of a complete digestive system over a gastrovascular cavity is that the complete system

Answer 7

allows specialized functions in specialized regions.

Question 8

For ingested foods, the first opportunity for enzymatic digestion occurs in the _____.

Answer 8

mouth

Question 9

The lower esophageal sphincter surrounds the upper opening into the stomach. If this sphincter failed to properly constrict, there might be a problem with _____.

Answer 9

regurgitation of acidic stomach contents into the esophagus, commonly called “heartburn”

Question 10

In the digestive system, peristalsis is

Answer 10

smooth muscle contractions that move food along the esophagus.

Question 11

Digestive secretions with a pH of 2 are characteristic of the

Answer 11

stomach.

Question 12

Pepsin is a digestive enzyme that

Answer 12

begins the hydrolysis of proteins in the stomach

Question 13

The cells that secrete the acidic components of stomach juices are

Answer 13

the parietal cells of the stomach

Question 14

Stomach cells are moderately well adapted to the acidity and protein-digesting activities in the stomach by having

Answer 14

a thick, mucous secretion and active mitosis of epithelial cells.

Question 15

The molar teeth of herbivorous mammals are especially effective at

Answer 15

grinding.

Question 16

Cattle are able to survive on a diet consisting almost entirely of plant material because

Answer 16

they have cellulose-digesting, symbiotic microorganisms in chambers of their stomachs.

Question 17

) When the digestion and absorption of organic molecules results in more energy-rich molecules than are immediately required by an animal, the excess is

Answer 17

stored as glycogen in the liver and muscles.

Question 18

Which of the following organs is incorrectly paired with its function?

Answer 18

large intestine-bile production

Question 19

After surgical removal of an infected gallbladder, a person must be especially careful to restrict dietary intake of

Answer 19

Fat

Question 20

Certain nutrients are considered “essential” in the diets of some animals because

Answer 20

these animals are not able to synthesize these nutrients

Question 21

An advantage of a complete digestive system over a gastrovascular cavity is that the complete system

Answer 21

allows for specialized regions with specialized functions.

Question 22

The natural antacid that protects the intestines against stomach acid is produced by the ______.

Answer 22

pancrease

Question 23

absorption

Answer 23

the third stage of food processing in animals; the uptake of small nutrient molecules by an organism’s body

Question 24

alimentary canal

Answer 24

A complete digestive tract, consisting of a tube running between a mouth an an anus

Question 25

An advantage of a complete digestive system over a gastrovascular cavity is that the complete system

Answer 25

allows for specialized regions with specialized functions.

Question 26

Cattle are able to survive on a diet consisting almost entirely of plant material because

Answer 26

they have cellulose- digesting, symbiotic microorganisms in chambers of their stomachs.

Question 27

Choose the correct anatomical sequence that presents the order in which food in the digestive system passes through.

Answer 27

pharynx → esophagus → stomach → small intestine → large intestine

Question 28

digestion

Answer 28

The second stage of food processing in animals; breaking down of food into molecules small enough for the body to absorb

Question 29

duodenum

Answer 29

the first section of the small intestine, where chynne from the stomach mixes with digestive juices from the pancreas, liver and gallbladder as well as from gland cells of the intestinal wall

Question 30

elimination

Answer 30

the fourth and final stage of food processing in animals; the passing of undigested material out of the body

Question 31

essential amino acid

Answer 31

an amino acid that an animal cannot synthesize itself and must be obtained from food in prefabricated form

Question 32

Essential fatty acid

Answer 32

an unsaturated fatty acid that an animal needs but cannot make

Question 33

essential nutrient

Answer 33

a substance that an organism cannot synthesize from any other material and therefore must absorb in preassembled form

Question 34

Fat digestion yields fatty acids and glycerol, whereas protein digestion yields amino acids; both digestive processes

Answer 34

add a water molecule to break bonds (hydrolysis).

Question 35

ingestion

Answer 35

the first stage of food processing in animals; the act of eating

Question 36

large intestine

Answer 36

The portion of the vertebrate alimentary canal between the small intestine and the anus; functions mainly in water absorption and the formation of feces

Question 37

leptin

Answer 37

A hormone produced by adipose cells that acts as a satiety factor in regulating appetite

Question 38

liver

Answer 38

A large internal organ in vertebrates that performs diverse functions, such as producing bile, maintaining blood glucose levels and detoxifying poisonous chemicals in the blood

Question 39

microvillus

Answer 39

one of many finger-like projections of the epithelial cells in the lumen of the small intestine that increase its surface area

Question 40

mineral

Answer 40

In nutrition, simple nutrient that is inorganic and therefore cannot by synthesized in the body

Question 41

Pancreas

Answer 41

A gland with exocrine and endocrine tissues

Question 42

Pepsin

Answer 42

An enzyme present in gastric juice that begins the hydrolysis of proteins

Question 43

protease

Answer 43

an enzyme that digests proteins by hydrolysis

Question 44

ruminant

Answer 44

an animal, such as a cow or a sheep, with multiple stomach compartments specialized for the herbivorous diet

Question 45

Salivary glands

Answer 45

Salivary glands a gland associated with the oral cavity that secretes substances that lubricate food and begin the process of chemical digestion

Question 46

Small intestine

Answer 46

The longest section of the alimentary canal; the principal site of the enzymatic hydrolysis of food and macromolecules

Question 47

Stomach

Answer 47

an organ of the digestive system that stores food and performs preliminary steps of digestion

Question 48

The "essential nutrients" for proper human nutrition include _____.

Answer 48

calcium, sodium, potassium, and other minerals

Question 49

vitamin

Answer 49

an organic molecule required in the diet in very small amounts

Question 50

Which pair correctly associates a physiological process with the appropriate vitamin? A) blood clotting and vitamin C B) normal vision and vitamin A C) synthesis of cell membranes and vitamin D D) protection of skin from cancer and vitamin E E) production of white blood cells and vitamin K

Answer 50

normal vision and vitamin A

Question 51

``` The fat-soluble vitamins include A) vitamin A. B) vitamin B12. C) vitamin C. D) iodine. E) calcium. ```

Answer 51

vitamin A, D, E, & K

Question 52

A mineral that is especially important for preventing anemia is

Answer 52

iron

Question 53

Folic acid supplements have become especially important for pregnant women because

Answer 53

folic acid deprivation is associated with neural tube abnormalities in a fetus.

Question 54

) Excessive iron absorption and accumulation to toxic levels is associated with

Answer 54

the genetic disorder known as hemochromatosis

Question 55

Earthworms, grasshoppers, and birds all have a

Answer 55

crop

Question 56

Because the foods eaten by animals are often composed largely of macromolecules, this requires the animals to have mechanisms for

Answer 56

enzymatic hydrolysis

Question 57

After ingestion by humans, the first category of macromolecules to be chemically digested by enzymes in the mouth is

Answer 57

carbohydrates

Question 58

Salivary amylase digests

Answer 58

starch

Question 59

Among mammals, it is generally true that A) all types of foods begin their enzymatic digestion in the mouth. B) after leaving the oral cavity, the bolus enters the larynx. C) the epiglottis prevents swallowed food from entering the trachea. D) the esophagus is a key source of digestive enzymes. E) the trachea leads to the esophagus and then to the stomach.

Answer 59

the epiglottis prevents swallowed food from entering the trachea

Question 60

Upon activation by stomach acidity, the secretions of the parietal cells

Answer 60

initiate the digestion of protein in the stomach.

Question 61

An enzyme with high activity in an acidic environment is

Answer 61

pepsin.

Question 62

The cells that secrete acidic fluid in the stomach are

Answer 62

in the lumen of the stomach

Question 63

A fasting animal whose energy needs exceed those provided in its diet draws on its stored resources in which order?

Answer 63

liver glycogen, then muscle glycogen, then fat