Abeka Health Grade 9 Section 1.2

Digestion

The physical and chemical breakdown of complex nutrients into simpler, water-soluble substances the body can use

Crown

The part of the tooth you see

Enamel

The hardest substance in the body

Dentin

Hard bone-like tissue

Pulp

The hollow center of the tooth that is filled with a soft tissue

Root canal

An opening at the tip of a tooths root through which nerves and blood vessels enter the tooth

Cementum

A thin bone-like covering over the root helps hold the tooth firmly in its socket

Periodontal membrane

The layer of tissue that produces cementum

Gingiva

Gum; the tissue surrounding the teeth

Tounge

A muscular organ that forms the softened food into a ball and then pushes it to the back of the mouth

Pharynx

Throat

Uvula

A small muscular flap of tissue suspended at the back of your mouth that closes the opening to your nasal passages

Epiglottis

A small flap of cartilage thag closes over the top of the trachea to prevent the food from entering your respiratory tract.

Enzymes

Protein molecules designed to activate or speed up chemical reactions in your body.

Saliva salivary glands

A digestive juice containing water, mucus, and a digestive enzyme

Esophagus

A muscular tube that connects the pharynx to the stomach.

Peristalsis

Two layers of involuntary muscles that produce wavelike contractions

Gastrointestinal tract

The digestive tract

Sphincter muscle

Circular bands of muscle located where the esophagus joins the stomach and allow food to pass into the stomach

Stomach

A muscular, sac-like organ

Gastric juice

A mixture of hydrochloric acid, digestive enzymes, and mucus

Chyme

A thick liquid that that mixes the food particles with gastric juice to change the food.

Mucous membrane

Coated with mucus to protect the stomach from digestive enzymes and the corrosive action of the acid

Small intestine

The longest part of the digestive tract

Duodenum

The first 10 inches of the small intestine

Villi

Tiny hairlike projections that give the inner surface of the small intestine a velvety appearance

Jejunum

The middle section of the small intestine.

Ileum

The longest part of the small intestine into the colon

Colon

Large intestine

Appendix

A fingerlike projection that has no known function in digestion

Feces

Semisolid wate material

Rectum

The last few inches of the digestive tract

Liver

The largest internal organ of the body

Bile

Digestive juice that is essential for breaking down fats and oils.

Carbohydrates

Sugars and starches

Simple carbohydrates

Monosaccharides and disaccharides

Complex carbohydrates

Polysaccharides formed from long chains of simple carbohydrates

Dietary fiber

Good sources of carbohydrates

Cholesterol

A fatlike substance that can accumulate in blood vessels and restrict blood flow

Proteins

Amino acids

Amino acids

Long chains of building blooks

Essential amino acids

An amino acid that the body cannot manufacture and must obtain from food

Incomplete proteins

Lack in essential amino acids

Fatty acids

Chains of carbon, hydrogen, and oxygen attached to a gylcerol molecule

Triglycerides

Typical fat molecules consist of three fatty acids

Lipids

A general term for fatlike substances that are typically insoluble water

Saturated fatty acids

Fatty acids that hold as many hydrogen atoms as possible

Unsaturated fatty acids

Hold fewer hydrogen atoms than saturated fatty acids

Lipoproteins

Fat and other lipids are transported through the bloodstream in “packages” of fats and protein

Vitamins

Important organic substances in foods that are needed in small amounts so that body cells and tissues can function properly

Antioxidants

Substances that neutralize harmful molecules called free radicals

Water solubles

Vitamins C and B complex

Deficiency disease

Caused by the lack of some substance in the diet.

Enriched foods

Processed foods restored by adding vitamins during processing

Fat-soluble vitamins

Vitamins A, D, E, and K

Hypervitaminosis

Toxic levels of certain vitamins by consuming too many vitamin supplements

Minerals

Inorganic substances needed in small amounts for body cells and tissues to function properly

Magnesium

Vital to energy production

Electrolytes

Potassium, sodium, and chlorine

Trace elements

Minerals that are important in the diet but are needed in only minute quantities

Water

The primary component of all body fluids; essential for digesting and absorbing food, transporting nutrients to the body's cells, removing waste from the cells, and building and repairing cells