Transcript Digestive System

Digestive System
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