Digestive System Vocab

Front 1

Accessory organs

Back 1

Term often used to refer to the pancreas, liver, and gall bladder, because their role in the process of digestion is vital, but they are not physically part of the digestive tract.

Front 2

Amylase

Back 2

Enzyme in saliva that breaks down starch into simpler sugars.

Front 3

Catalyst

Back 3

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

Front 4

Hydrolysis

Back 4

Chemical reaction in which the addition of a water molecule cleaves a macromolecule into subunits; one hydrogen atom from water and is attached to one subunit and a hydroxyl group is bonded to the other subunit, breaking a covalent bond in the macromolecule.

Front 5

Chyme

Back 5

Thick liquid formed by mixing food with gastric juice in the stomach.

Front 6

Digestive tract

Back 6

In animals, a long tube that extends from the mouth to the anus, through which food moves and is broken down into simpler compounds that are used for energy, growth, and cell repair.

Front 7

Bolus

Back 7

Smooth, lump-like mass of food rolled by the tongue to aid swallowing.

Front 8

Macromolecule

Back 8

A large, complex assembly of organic molecules; four categories of macromolecules are carbohydrates, lipids, proteins, and nucleic acids.

Front 9

Disaccharide

Back 9

Sugar that can be hydrolysized into two monosaccharides subunits; examples include maltose and sucrose.

Front 10

Monosaccharide

Back 10

Simple sugar that cannot be hydrolyzed into simpler sugars; for example glucose, fructose, and galactose.

Front 11

Dehydration synthesis

Back 11

Chemical reaction that results in the formation of a covalent bond between two subunit molecules by the removal of an –OH (hydroxyl) group from one subunit and a hydrogen atom from the other subunit; essentially, a molecule of water (H2O) is removed.

Front 12

Gall bladder

Back 12

Organ that stores bile produced by the liver.

Front 13

Homeostasis

Back 13

The tendency of the body to maintain a relatively constant internal environment.

Front 14

Bioavailability

Back 14

The amount of a nutrient that a person absorbs from a source, rather than the total amount actually in the source.

Front 15

Pancreas

Back 15

Small gland in the abdomen that secretes digestive enzymes into the small intestine, as well as bicarbonate to neutralize hydrochloric acid from the stomach; also secretes the hormone insulin.

Front 16

Inhibitor

Back 16

Molecule that attaches to an enzyme and reduces its ability to bind substrate; two classes are competitive and non-competitive inhibitors.

Front 17

Peristalsis

Back 17

Wave-like series of muscular contractions ad relaxations of the circular and longitudinal muscles that surround the various parts of the digestive tract; aids the movement of food through the digestive tract.

Front 18

Polysaccharide

Back 18

Complex carbohydrate consisting of many simple sugars linked together; examples include starch, cellulose, and glycogen.

Front 19

Triglyceride

Back 19

High-energy organic molecule composed of one glycerol molecule and three fatty acid molecules; main component of fats and oils.

Front 20

Villus (villi)

Back 20

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

Front 21

Essential amino acid

Back 21

Refers to the any of the nine of twenty amino acids that must come from the diet because the human body cannot synthesize them.

Front 22

Nucleic acid

Back 22

Macromolecule formed from a long chain of nucleotide subunits, each consisting of a five-carbon simple sugar, a nitrogen-containing base, and a phosphate group; two types include DNA and RNA.

Front 23

Esophagus sphincter

Back 23

A muscular ring between the esophagus and the stomach that controls the movement of food into and out of the stomach

Front 24

Liver

Back 24

Organ found in the abdomen that performs hundreds of functions as an accessory organ of the digestive system, including the secretion of bile to digest fats; other functions include plasma protein production, blood detoxification, and glycogen storage

Front 25

Gastrin

Back 25

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

Front 26

Lipase

Back 26

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

Front 27

Carbohydrases

Back 27

Enzyme that catalyses the hydrolysis of carbohydrates.

Front 28

Gastric Juices

Back 28

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

Front 29

Segmentation

Back 29

The subdivision of an organism or of an organ into more or less equivalent parts.