Human Body Systems

Human Body Systems

Human Body Organization
The Human Body is composed of

Organ Systems are composed of

Organs are composed of

Tissues are composed of

Cells

DIGESTIVE SYSTEM is a body system made up of digestive tract and glands responsible for digestion of food. Functions of
Digestive System:
 Digestion of food.
 Breaking down of chunks of food into bits.
 Absorption of food nutrients.
 Excretion of undigested food.

PARTS OF DIGESTIVE SYSTEM.

Digestive Glands
 Salivary Gland – secrete saliva for lubrication of food.
 Gastric Gland – secrete gastric juice for lubrication of food and digestion of protein and fats.
 Intestinal Gland – secrete intestinal juice for breaking down of food molecules and nutrients.  Pancreas- secrete pancreatic juice for digestion of fatty acids and glycerol.
 Liver – secrete bile (located in the gall bladder) which emulsifies fat into fat globules. THE DIGESTIVE PROCESS
The digestive process starts in the MOUTH where food is partly broken down by the process of chewing and grinding by the help of the chemical action of salivary enzymes. After being chewed and swallowed, the food enters the ESOPHAGUS, a long tube that runs food from the mouth to the stomach through the help of a wave-like muscle movement called peristalsis. The STOMACH is a large, sack-like organ that blends the food with a very strong gastric acid. After being in the stomach, food enters the SMALL INTESTINE, where bile
(produced in the liver and stored in the gall bladder), pancreatic enzymes and other digestive enzymes produced by the inner wall of the small intestine which help in the breaking down of food. After passing through the small intestine, food passes into the LARGE
INTESTINE, where some of the water and electrolytes (chemicals like sodium) are removed from the food. Then, the undigested food will be stored in the RECTUM until it is

FOUR STAGES OF DIGESTIVE
PROCESS
 Ingestion (the process of taking food and drink into the body).
