Digestive System

Function: organs that aid in the digestion (break down) of “food” into substances that cells can absorb.

Digestive System -Teeth (mechanical digestion) Salivary glands (chemical digestion) 1) Epiglottis - small flap of tissue that prevents food from entering the windpipe. 2) Esophagus – muscular tube that connects the mouth to the stomach -Peristalsis – wavelike contraction of the muscles that moves food (bolus) through the digestive system 3) Stomach – saclike organ of digestion, made up of 3 layers of muscles that twist, turn and churn food. Food is mixed with gastric juices -Most food remains in stomach for 3-4 hours. Food is changed into a thick liquid called chyme. 5) Duodenum – connects stomach to small intestine, about 1 foot long and shaped like a “C”. Major digestion begins here.

Digestive System (P) Pancreas – long, soft gland lying behind the stomach that secretes digestive enzymes into the duodenum 4) Liver – large organ that secretes bile, filters the blood, and stores carbohydrates. Blood containing nutrients travel from small intestine to liver 6) Small intestine – most digestion and absorption of food occurs in small intestine. Long coiled about 1” in diameter. -Villa – very tiny fingerlike projections lining the walls of the small intestine. Inside villa are blood vessels and vessels containing lymph. -Blood and lymph then carry completely digested food throughout the body 7) Large intestine (colon) – about 5 feet long. Major function is to reabsorb water, so remaining waste becomes solid. The remaining solid are called feces or stool. 8) Rectum – stores solid waste until the body is able to expel them.

Digestive Disorders Constipation – difficult or non-frequent bowel movements. – Change diet, drink more water or exercise Diarrhea – feces are watery and loose and bowels move too often. Large intestine does not reabsorb enough water. Indigestion – inability of body to digest food properly. Lactose intolerance – lack of enzyme needed to digest milk sugar or lactose. Appendicitis – appendix becomes inflamed, swollen and filled with puss. Hernia – digestive organ protrudes from abdominal wall

Digestive Disorders Hemorrhoids – swollen veins in the anal area. Gallstones – hard, stonelike substance that are formed from cholesterol and other substance in the bile. Ulcers – open sores that form in different parts of the body Crohn’s disease – chronic disease of small intestine. Nutrients are not absorbed for the small intestine and the person suffers from malnutrition. Ulcerative colitis – inflammation of the lining of the colon Cancer – pancreas, stomach, colon and rectum. Colon cancer = third most common type of cancer