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

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 & churningChemical: digestive juices

Mouth (carbohydrates) Stomach (proteins) Small Intestine (fats)

Parts of the Digestive system

TeethSalivary Glands

EsophagusStomach

LiverGallbladder

PancreasSmall Intestine

Large Intestine (Colon)Rectum

Anus

Mouth

Teeth:Mechanical breakdown of foods

Salivary Glands: Chemical breakdown of carbohydrates

(starches & sugars)

StomachGastric Juices breakdown proteins:

1. Hydrochloric acid2. 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 Liver2. stored in Gallbladder

• Also changes toxins (poisons) into harmless substances.

• Examples of Body’s Toxins1. Poisonous Foods, Plants, Animals2. 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 fats2. All undigested food is broken down3. Most nutrients absorbed

Large Intestine5-6 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 ProblemsUlcers

Open sores in the mucous membrane of the GI tractIndigestion

Overwhelming of the stomachHeart burn

Stomach acid passes up to the esophagusGallstones

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