1. Here They Are: Your Body Systems (Part 1).

2. And Your Body Systems (Part 2)

3. DR. I.I.L. MCSNEER Presents… Your Digestive System

4. Your digestive system is like a complicated chemical processing plant, and performs many functions.

5. What major tasks does your digestive system help you accomplish?

6. Digestive System
1. breaks down food into molecules the body can absorb.
2. passes these molecules into the blood to be carried throughout the body.
3. works to eliminate solid wastes from the body.

7. Parts of Your Digestive System
                                         

8. Now for the Digestive Journey

9. The Digestive Journey
Digestion begins in your mouth with action of your teeth and tongue (mechanical digestion) and your salivary glands (chemical digestion).
The salivary glands produce enzymes that are mixed with the food, breaking down the starches. Peristalsis is the muscular action that moves the food through the esophagus and into your stomach after you swallow.

10. Your Stomach
The food moves into your stomach, which contains chemicals such as hydrochloric acid and pepsin. Pepsin breaks proteins, and other enzymes break down fat. Your stomach gradually releases these materials into the upper small intestine (duodenum), where digestion is completed. Your stomach also has a thick coating of mucus to protect it form the acids and to keep it from digesting itself!

11. By the way, your stomach really does look like a muscular bag!

12. Your Liver, Pancreas, and Gall Bladder
Located in the upper portion of your abdomen, your liver is the largest and heaviest organ of your body. It is like a busy chemical factory that plays many roles. For example, your liver breaks down many substances and toxins, and produces bile- a substance that helps break down fat. The bile flows from the liver into the gall bladder, where it is stored until needed. The pancreas lies between the stomach and the duodenum and produces enzymes that flow into the small intestines, helping to break up complex starches, proteins, and fats.

13. Your Small & Large Intestines
After the solid food has been digested the fluid remaining is called chyme When it is thoroughly digested it passes through an opening (called the pylorus sphincter) into the small intestines. In the small intestines all the nutrients are absorbed leaving undigestible wastes. These wastes pass into the large intestines, where water is removed. Then the wastes are stored in the rectum until they are released by the anus.

14. DR. I.I.L. MCSNEER Presents… Your Excretory System
Your excretory system collects wastes produced by cells and removes these wastes from your body. The removal process is known as excretion. The two kidneys are the major organs of the excretory system. The kidneys filter your blood and remove urea, excess water, and some other waste materials from your blood. Urea is a chemical that comes from the breakdown of proteins. The filtering process produces a watery fluid called urine. Each kidney contains about a million nephrons.