Concepts and Applications, Chapter 36

Interactions among digestive, circulatory, respiratory, and urinary systems supply the body’s cells with raw materials and dispose of wastes

Most digestive systems have regions for transport, processing, and storage

To maintain an acceptable body weight, energy intake must balance energy output by way of metabolic activity and physical exertion

Nutrition involves the intake of foods, vitamins, and minerals

Mechanical processing and motility

Secretion of enzymes

Digestion

Absorption

Elimination

Mouth

Pharynx

Esophagus

Stomach

Small intestine

Large intestine

Rectum

Anus

Accessory Organs

Salivary glands

Liver

Gallbladder

Pancreas

Mix food

Protein digestion

Controls passage of food

Gastric fluid

HCl Pepsin Mucus Chyme

Three regions

Duodenum

Jejunum

Ileum

Secreted by liver

Stored in gallbladder

Function

Emulsification of fats

Main absorption site

Passive and active transport

Micelle formation

Large folds

Villi Microvilli

Movement of substances

Peristalsis

Segmentation

Colon

Appendix

Conditions

Constipation

Appendicitis

Cancer

Nutrition refers to the processes by which the body takes in, digests, absorbs, and uses food

A complete digestive system includes a tube that connects a mouth to an anus and regional specializations between them

Mechanical and chemical processing of foods begins in the mouth and continues throughout certain structures

Starch digestion starts at the mouth, and protein digestion starts in the stomach

In absorption, cells of the intestine actively transport glucose and most amino acids out of the gut lumen

The nervous and endocrine systems, and neurons in the gut wall, interact to govern the digestive system