Chapter 17 Digestive System

A set of vocabulary flashcards based on the key terms and concepts from Chapter 17 on the Digestive System.

Digestion

The mechanical and chemical breakdown of foods into forms that cell membranes can absorb.

Mechanical Digestion

Breaks down large pieces of food into smaller ones without changing the chemical composition.

Chemical Digestion

Uses enzymes to break down food particles into simpler chemicals.

Alimentary Canal

The food passageway consisting of organs extending from the mouth to the anus.

Accessory Organs

Organs that empty secretions into the alimentary canal but food does not pass through them.

Salivary Glands

Secrete saliva, which contains enzymes that begin the breakdown of carbohydrates.

Peristalsis

The wave-like contraction that moves food through the digestive tract.

Mucosa

The innermost layer of the alimentary canal, which absorbs dietary nutrients and secretes mucus and enzymes.

Submucosa

A connective tissue layer containing blood and lymphatic vessels, nerves, and glands; nourishes surrounding tissues.

Muscularis (externa)

Layer containing circular and longitudinal muscle layers that move the alimentary canal and food materials.

Serosa

The outermost layer of the alimentary canal that provides protection and lubrication.

Chyme

A semifluid mass of partially digested food that is formed in the stomach.

Bolus

A mass of chewed food that is ready to be swallowed.

Gastric Juice

A mixture produced by gastric glands containing mucus, pepsinogen, hydrochloric acid, and intrinsic factor.

Bile

A yellowish-green liquid produced by the liver that emulsifies fats.

Cholecystokinin (CCK)

A hormone that stimulates gallbladder contraction and the release of bile.

Mastication

Mechanical breakdown of solid particles in the mouth through chewing.

Intrinsic Factor

A substance produced by parietal cells that is necessary for the absorption of vitamin B12.

Teeth

The hardest structures in the body used for breaking food particles into smaller pieces.

Gallstones

Solid crystals formed from the precipitation of cholesterol in the gallbladder.

Lacteals

Lymphatic capillaries in the intestinal villi that absorb fats.