Chapter 33

Question 1

Nutrition

Answer 1

The process by which an organism takes in and makes use of food substances
Unlike plants, animals must consume food for both energy and the organic molecules used to assemble new molecules, cells, and tissues.

Question 2

Vitamins

Answer 2

An organic molecule required in the diet in very small amounts. Many vitamins serve as coenzymes or parts of coenzymes

Question 3

Minerals

Answer 3

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

Question 4

Ingestion

Answer 4

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

Question 5

Digestion

Answer 5

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

Question 6

Absorption

Answer 6

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

Question 7

Elimination

Answer 7

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

Question 8

Alimentary Canal

Answer 8

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

Question 9

Amylase

Answer 9

An enzyme that hydrolyzes starch (a glucose polymer from plants) and glycogen (a glucose polymer from animals) into smaller polysaccharides and the disaccharide maltose

Question 10

Pharynx

Answer 10

An area in the vertebrate throat where air and food passages across

Question 11

Esophagus

Answer 11

A muscular tube that conducts food, by peristalsis, from the pharynx to the stomach

Question 12

Peristalsis

Answer 12

Alternating waves of contraction and relaxation in the smooth muscles lining the alimentary canal that push food along the canal

Question 13

Sphincter

Answer 13

A ringlike band of muscle fibers that controls the size of an opening in the body, such as the passage between the esophagus and the stomach

Question 14

Chyme

Answer 14

The mixture of partially digested food and digestive juices formed in the stomach

Question 15

Pepsin

Answer 15

An enzyme present in gastric juice that begin the hydrolysis of proteins. Pepsin is synthesized as an inactive precursor form, pepsinogen.

Question 16

Protease

Answer 16

An enzyme that digests proteins by hydrolysis

Question 17

Small Intestine

Answer 17

The longest section of the alimentary canal, so named because of its small diameter compared with that of the large intestine; the principal site of the enzymatic hydrolysis of food macromolecules and the absorption of nutrients.

Question 18

Duodenum

Answer 18

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

Question 19

Pancreas

Answer 19

A gland with exocrine and endocrine tissues. The exocrine portion functions in digestion, secreting enzymes and an alkaline solution into the small intestine via a duct; the ductless endocrine portion functions in homeostasis, secreting the hormones insulin and glucagon into the blood

Question 20

Bile

Answer 20

A mixture of substances that is produced in the liver and stored in the gallbladder; enables formation of fat droplets in water as an aid in the digestion and absorption of fats.

Question 21

Liver

Answer 21

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

Question 22

Gallbladder

Answer 22

An organ that stores bile and releases it as needed into the small intestine

Question 23

Villi

Answer 23

A finger-like projection of the inner surface of the small intestine

Question 24

Microvilli

Answer 24

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

Question 25

Hepatic Portal Vein

Answer 25

A large vessel that conveys nutrient-laden blood from the small intestine to the liver, which regulates the blood’s nutrient content

Question 26

Large Intestine

Answer 26

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 27

Colon

Answer 27

The largest section of the vertebrate large intestine; functions in water absorption and formation of feces.

Question 28

Cecum

Answer 28

The blind pouch forming one branch of the large intestine

Question 29

Appendix

Answer 29

A small, finger-like extension of the vertebrate cecum; contains a mass of white blood cells that contribute to immunity.

Question 30

Rectum

Answer 30

The terminal portion of the large intestine, where the feces are stored prior to elimination

Question 31

Ruminants

Answer 31

A cud-chewing animal, such as a cow or a sheep, with multiple stomach compartments specialized for an herbivorous diet

Question 32

Metabolic Rate

Answer 32

The total amount of energy an animal uses in a unit of time

Question 33

Insulin

Answer 33

A hormone secreted by pancreatic beta cells that lowers blood glucose levels. It promotes the uptake of glucose by most body cells and the synthesis and storage of glycogen in the liver.

Question 34

Glucagon

Answer 34

A hormone secreted by the pancreas that raises blood glucose levels. IT promotes glycogen breakdown and release of glucose by the liver.

Question 35

Diabetes Mellitus

Answer 35

An endocrine disease marked by an inability to maintain glucose homeostasis. The type 1 form results from autoimmune destruction of insulin-secreting cells; treatment usually requires daily insulin injections. The type 2 form most commonly results from reduced responsiveness of target cells to insulin; obesity and lack of exercise are risk factors.