Download Digestive System

Digestive System
In your journal:
• For each system you will need:
– Systems Main Function & Organs
– Main Problems & Disease
– How to Best Care for this system
– Recent Findings & How it Interact with other
systems
Main Organs
Where does digestion begin?

Teeth – hold, tear, chew foods

Salivary glands – secretes juices into mouth

Tongue – moves food mass to back of mouth

Esophagus – passageway

Stomach – churns food & adds gastric juices

Small intestines – absorbs nutrients

Liver – produces digestive juice (bile)

Pancreas – adds more digestive juice for breakdown

Gall bladder – stores bile until needed, secrets into SI


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Large intestines – stores unused solid, water is absorbed
here
Rectum – holds solid waste, controls release
• Digestion time varies depending on the
individual. For most healthy adults, it's usually
between 24 and 72 hours. After you eat, it takes
about six to eight hours for food to pass through
your stomach and small intestine.
• Elimination of undigested food residue through
the large intestine usually begins after a total of
24 hours. Complete elimination from the body
may take several days.
Main Functions
• Break Down of food (mechanical & chemical)
• Absorption of nutrients
• Elimination of waste
Function: of Digestion
The Breakdown of food
into basic building blocks (nutrients)
Mechanical: chewing & churning
Chemical: digestive juices
Mouth (carbohydrates)
Stomach (proteins)
Small Intestine (fats)
Parts of the Digestive system
Teeth
Salivary Glands
Esophagus
Stomach
Liver
Gallbladder
Pancreas
Small Intestine
Large Intestine (Colon)
Rectum
Anus
Mouth
Teeth:
Mechanical breakdown of foods
Salivary Glands:
Chemical breakdown of carbohydrates
(starches & sugars)
Stomach
Gastric Juices breakdown proteins:
1. Hydrochloric acid
2. Pepsin (enzyme that digests protein)
Smooth Muscles in walls churn food to make
Chyme: Creamy mixture of
food and gastric juices
Sphincter @ entrance of stomach, prevents food
from backing up
Liver
• Bile: Greenish fluid breaks down Fats
1. made in Liver
2. stored in Gallbladder
• Also changes toxins (poisons) into harmless substances.
• Examples of Body’s Toxins
1. Poisonous Foods, Plants, Animals
2. Alcohol & Drugs (including medicines (ibuprofen…)
`Pancreas
Produces:
1. Insulin – a hormone that metabolizes
sugars in the blood
2. Digestive Enzymes - for fats and proteins
Small Intestine
21-23 feet long…and…1 inch in diameter
• Villi: finger-like projections in
the walls of the small intestine
lined with capillaries
(smallest vessels in the circulatory system).
1. Major digestion of fats
2. All undigested food is broken down
3. Most nutrients absorbed
Large Intestine
5-6 feet long…and
…2-3 inches in diameter
• Last Chance!!
Final nutrients pass into the blood stream
1. Water
2. Vitamins
3. Mineral Salts
Common Problems
 Ulcers
 Open sores in the mucous membrane of the GI tract
 Indigestion
 Overwhelming of the stomach
 Heart burn
 Stomach acid passes up to the esophagus
 Gallstones
 Crystallized deposits of cholesterol and other
substances that collect in the gallbladder
 Appendicitis
 Inflammation in the appendix, usually caused by
bacteria (lower right)
How to care FOR THIS SYSTEM:
•
•
•
•
•
Drink water
Eat healthy (variety & high fiber)
Avoid fatty foods
Eat food slowly
Don’t eat under stress
Foods that benefit the Digestive
System
• Yogurt,Apples, peaches carrots and
cabbage are especially helpful with lower GI
tract.
• To avoid constipation: (build up of stools
minus liquid)…oats, fruits, veggies, fiber rich
food
How it interacts with other
systems
• Circulatory/Cardiovascular
– takes nutrients from small intestine to rest
of body
• Muscular
– Muscles contract pushing food through
(peristalsis)
• Nervous
– Tells brain when you are hungry-
• Immune
– Acid in stomach kills pathogens