Chapter 6: Digestion and Human Health

Question 1

Dehydration Synthesis

Answer 1

A chemical reaction where -OH (hydroxyl) is taken from one subunit, and a hydrogen atom is taken from another subunit so the subunits can bond together.

Question 2

Hydrolysis

Answer 2

A chemical reaction where water is added to cause a macromolecule to split into two subunits. These subunits receive the -OH and H from the added water.

Question 3

Carbohydrate

Answer 3

An organic macromolecule that contains carbon, hydrogen, and oxygen in a 1:2:1 ratio.
Ex: monosaccharides, disaccharides, polysaccharides

Question 4

Lipid

Answer 4

Group of organic macromolecules, including fats, oils, phospholipids, and steroids.

Question 5

Protein

Answer 5

Organic macromolecule assembled from subunits of amino acids.

Question 6

Peptide Bond

Answer 6

Bond between the amino group of one amino acid and the carboxyl group of another in a protein.

Question 7

Nucleic Acid

Answer 7

Macromolecule formed from a long chain of nucleotide subunits. The two types include DNA and RNA.

Question 8

Vitamin

Answer 8

Organic compound required in trace amounts for normal metabolism.

Question 9

Mineral

Answer 9

Inorganic compound required in trace amounts for normal metabolism.

Question 10

Catalyst

Answer 10

A chemical that speeds up a chemical reaction but is not used up in the reaction.

Question 11

Enzyme

Answer 11

Protein molecule that acts as a catalyst to increase the rate of a reaction.

Question 12

Digestive System

Answer 12

The system into which food is taken and broken down so that useful substances can be absorbed into and transported by the circulatory system to individual cells.

Question 13

Mouth

Answer 13

The opening in which food enters the body. Chews and mixes food with saliva and sends it to the esophagus as the bolus.

Question 14

Amylase

Answer 14

Enzyme in saliva that breaks down starch into simpler sugars.

Question 15

Esophagus

Answer 15

Direct food (bolus) from the mouth to the stomach.

Question 16

Peristalsys

Answer 16

Wavelike series of muscular contractions and relaxations. This causes a substance to be moved.

Question 17

Esophageal Sphincter

Answer 17

A ringlike muscular structure that controls foods entry to the stomach.

Question 18

Macromolecule

Answer 18

A complex assembly of organic molecules.

The four categories of macromolecules are carbohydrates, lipids, proteins, and nucleic acids.

Question 19

Stomach

Answer 19

J-shaped sac lying between the esophagus and the small intestine whose muscles ad secretions work to physically and chemically break down food and push it into the small intestine.

Question 20

Pyloric Sphincter

Answer 20

Controls the exit of the stomach’s contents into the small intestine.

Question 21

Pepsin

Answer 21

A protein digesting enzyme that is secreted into the stomach. It remains inactive until hydrochloric acid is present.

Question 22

Small Intestine

Answer 22

Made of the duodenum, jejunum, and ileum. The part of the digestive tract between the stomach and the large intestine. Its main function is to complete the digestion of macromolecules and absorb their subunits.

Question 23

Segmentation

Answer 23

The process by which some physical digestion occurs in the small intestine. Chyme sloshes back and forth in the small intestines breaking up macromolecules.

Question 24

Duodenum

Answer 24

First section of the small intestine. Important for chemical digestion of chyme from the stomach.

Question 25

Villi

Answer 25

Finger-like projections along the ridges of the small intestine; increases surface area to aid in the absorption of nutrients.

Question 26

Microvilli

Answer 26

Projections that greatly increase the cells surface area. They are found on the villi of the small intestine and on the membranes of certain cells.

Question 27

Pancreas

Answer 27

Small gland that secretes digestive enzymes into the small intestine, as well as bicarbonate to neutralize hydrochloric acid from the stomach.

Question 28

Liver

Answer 28

An accessory organ of the digestive system which secretes bile to digest fats.

Question 29

Gall Bladder

Answer 29

Organ that stores bile produced by the liver.

Question 30

Carbohydrase

Answer 30

Enzyme that catalyses the hydrolysis of carbohydrates.

Question 31

Lipase

Answer 31

Enzyme that catalyses the hydrolysis of triglycerides into glycerol and fatty acids.

Question 32

Protease

Answer 32

Enzyme that hydrolyzes the peptide bonds that link amino acids in proteins and peptides.

Question 33

Nuclease

Answer 33

Enzyme that hydrolyses the bonds between nucleotides in the nucleic acids.

Question 34

Gastrin

Answer 34

Stomach hormone that stimulates the secretion of hydrochloric acid and the inactive precursor molecule of pepsin from glands in the stomach.

Question 35

Secretin, CCK, GIP

Answer 35

Enables fatty meals to stay in the stomach longer than non-fatty meals. Also stimulates the pancreas to release more bicarbonate to neutralize acidic chime.

Question 36

Ulcer

Answer 36

Slow-healing sore that forms when the thick layer of mucus that protects the lining of the stomach from the acids in digestive juices is eroded.

Question 37

Inflammatory Bowel Disease

Answer 37

Disease that causes inflammation in the intestines (bowels). Examples are Crohn’s disease and colitis.

Question 38

Hepatitis

Answer 38

Inflammation of the liver tissue.

Question 39

Cirrhosis

Answer 39

A disorder of the liver in which scar tissue replaces healthy liver tissue and prevents the liver from functioning properly.

Question 40

Gallstone

Answer 40

Small, hard mass that forms in the gall bladder when cholesterol precipitates out of the bile and forms crystals that grow in size.

Question 41

Anorexia Nervosa

Answer 41

Eating disorder characterized by a morbid fear of gaining weight and misconception of body image.

Question 42

Obesity

Answer 42

Condition in which body mass is 20 percent or more above what is considered to be an ideal body mass for a person’s height.