The Digestive System

digestion

The process by which the body breaks down food into small nutrient molecules

Absorption

The process by which nutrient molecules pass through the wall of the digestive system into the blood

saliva

the enzyme in the mouth that changes STARCH to SUGAR

enzyme

A type of chemical (a protein) that breaks down food into smaller molecules.

Epiglottis

A flap of tissue that seals off the windpipe and prevents food from entering.

Esophagus

A muscular tube that connects the mouth to the stomach.

mucus

A thick, slippery substance produced by the body

Peristalsis

Involuntary waves of muscle contraction that keep food moving along in one direction through the digestive system.

stomach

A J-shaped, muscular pouch located in the abdomen.

small intestine

The part of the digestive system in which MOST chemical digestion takes place.

liver

The largest organ in the body; and produces bile.

Bile

A substance produced by the liver that breaks up fat particles.

Gallbladder

the organ that stores bile after it is produced by the liver

Pancreas

A triangular organ that lies between the stomach and first part of the small intestine. It produces enzymes that break down starches, proteins, and fats.

villi

Tiny finger-shaped structures that cover the inner surface of the small intestine and provide a large surface area through which digested food is absorbed

large intestine

The last section of the digestive system, where water is absorbed from food and the remaining material is eliminated from the body

Rectum

The end of the large intestine where waste material is compressed into a solid form before being eliminated

anus

A muscular opening at the end of the rectum through which waste material is eliminated from the body

chemical digestion

Enzymes break down food into smaller molecules

mechanical digestion

Physical breakdown of large pieces of food into smaller pieces

Chyme

thick liquid form of food

gastric juice

juice produced in the stomach that contains mucus, pepsin, and hydrochloric acid

Pepsin

enzyme that digests proteins

Bile

is a substance that PHYSICALLY breaks up large fat droplets into smaller fat droplets

colon

another name for the large intestine

nutrients

Substances in food that your body NEEDS to grow, to repair itself, and to supply you with energy

bolus

slippery mass (ball of food) formed in the mouth then gets swallowed

pharynx

throat; passageway for food to the esophagus and air to the larynx

lipid

Energy-rich organic compounds, such as FATS & oils,

Carbohydrates

nutrient that supplies ENERGY and can be broken down into sugar (glucose) and starches

feces

solid wastes; stool

Starch

is a complex carbohydrate found in foods from plants such as potatoes, rice, wheat, and corn

Protein

is a nutrient made up of amino acids. Ex: animal sources, such as meat & eggs. Also plant sources, such as beans, grains, and nuts.

Lipase

an enzyme that breaks down fat (lipids)