NUSCTX 10 Chapter Notes - Chapter 3: Gastric Pits, Amylase, Laboratori Nazionali Del Gran Sasso
Document Summary
Hormones: chemical messengers that are produced in one location, released into the blood and elicit responses at other locations in the body. Digestion: process of brekaing food into components small enough to be absorbed into the body. Absorption: process of taking substances into interiror of the body. Feces: body waste, including unabsorbed food residue, bacteria, mucus and dead cells (moves through gastrointestinal tract) Gastrointestinal tract: hollwo tube consisting of the mouth pharynx, esophagus, stomach, small intestine, large intestine and anus, in which digestion and absorption of nutrients occurs. Food in the lumen has not been absorbed so techically outside the body. Transit time: time between ingestion of food and elimination of solid waste from that food (24-72 hours) Lining of the lumen is mucosa, a layer of mucosal cells that serves as protective layer and is responsible for absorption of end products of digestion. Mucosa cells in direct contact with food and harsh digestive secretions so have short life spans.