Download The_Digestive_System - Effingham County Schools

The Digestive System
Structures
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Esophagus
Stomach
Small Intestine
Large Intestine(colon or bowel)
– Rectum
– Anus
• Liver
• Pancreas
• Gall Bladder
Function
• To break down food into smaller portions that
can be absorbed into the bloodstream and
delivered to the cells of the body.
• This process is called DIGESTION.
2 types of digestion: chemical and
mechanical
– Mechanical digestion mashes and grinds
food into smaller pieces.
• Stomach, teeth, tongue use mechanical
digestion
– Chemical digestion is the breaking down of
food into molecules
• Stomach, small intestine, and saliva use
chemical digestion.
More on digestion
• Begins in the mouth
• Most occurs in the small intestine
The digestive tract
Food passes through the digestive tract
Includes the mouth, esophagus, stomach,
small intestine, large intestine
Esophagus
• Muscular tube that connects the pharynx
(throat) to the stomach
Stomach
• Muscular, sac like organ
• Uses chemical and mechanical digestion to
break down food
• Contains acid and enzymes to break down
food and kill bacteria you may swallow
Small Intestine
• Smaller in diameter; longer in length
• Most digestion occurs here
• Lined with villi that increase surface area for
nutrient absorption
• Nutrients are absorbed in the bloodstream
here
Large Intestine
• Stores, compacts, and eliminates waste
products
• Fiber helps to keep the stool(poop) soft and
moving through
• Last part is the rectum
– Stores feces(poop) until it can be eliminated from
the body
– Opening is called the anus
Liver
• Not part of the DIGESTIVE TRACT aids in
digestion
• Makes bile
• Stores and absorbs nutrients
• Breaks down toxins
Gall Bladder
• Not part of the DIGESTIVE TRACT aids in
digestion
• Stores bile that is made in the liver
Pancreas
• Not part of the DIGESTIVE TRACT aids in
digestion
• Neutralizes stomach acids
– The body’s natural antacid (like Tums)
• Produces enzymes that aid in digestion
• Also part of the endocrine system