Chapter 6

Digestion

The process of breaking down food into smaller, absorbable components.

Gastrointestinal tract

A flexible, muscular tube that extends from the mouth to the anus.

Peristalsis

Involuntary muscle contractions that propel food through the GI tract.

Segmentation

Periodic squeezing of intestines that enhances contact with digestive juices.

Chyme

A semi-liquid mass of partly digested food that is released from the stomach into the small intestine.

Lipoproteins

Molecules made of fat and protein that transport lipids through the bloodstream.

Villi

Fingerlike projections in the small intestine that increase surface area for nutrient absorption.

Salivary amylase

An enzyme secreted in saliva that begins the digestion of carbohydrates.

Bile

A digestive fluid produced by the liver, stored in the gallbladder, that emulsifies fats.

Foodborne illness

Illness caused by consuming contaminated foods or beverages.

Homeostasis

The process by which the body maintains a stable internal environment.

Nutrient absorption

The process by which nutrients from digested food are taken into the bloodstream.

Gastric juices

Acidic digestive fluids secreted by the stomach that contain enzymes and hydrochloric acid.

Bicarbonate

A compound secreted by the pancreas that neutralizes stomach acid in the small intestine.

Chylomicrons

A type of lipoprotein that transports dietary lipids from the intestines to other locations in the body.