1. By: Madison, Amber and Rene Grade: 10 Health Science 20
Digestive System
By: Madison, Amber and Rene
Grade: 10
Health Science 20

2. Major Function of The Digestive System
The main function of the digestive system is to absorb and digest the food we eat. It is divided into two major parts, the digestive tract and the accessory organs.
1. Digestive Tract
Also known as the alimentary canal, has two openings and is an ongoing tube. The openings include the mouth and the anus and the ongoing tube includes everything in between.
2. Accessory Organs
Are the organs that help absorb the nutrients from the food and help digest the food but are not part of the actual digestive tract.

3. Functions of The Organs in The Digestive System
1. Mouth
Food begins its long journey through the system in the mouth where the teeth chop up the food into small pieces and saliva moistens the food to be swallowed into the pharynx.
2. Pharynx
The pharynx, also known as the throat, is a funnel shaped tube connected to the back part of the mouth that passes food from the mouth to the esophagus. It has a dual purpose of letting air through the nasal cavities so it contains a flap of tissue that acts as a switch route of both the food and air.

4. 3. Esophagus
The esophagus is a tube full of muscles that pushes food from the pharynx into the stomach. At the end of the esophagus is a muscular ring to close the end of the esophagus and trap food in the stomach.
4. Stomach
The stomach is a muscular sac on the left side of the abdominal cavity. It acts as a place for the food to “wait” while the body digests large meals properly. It also contains hydrochloric acid and digestive enzymes that continue digestion of the food while it stays in the stomach.

5. Stomach Continued
The stomach is crescent shaped and roughly the size of two fists put together. It weighs around two pounds because of the amount of muscles within the stomach, but weighs even more when filled with food. It is located between esophagus and the first part of the small intestine (or the duodenum). The inner layer is full of gastric folds that allow the stomach to stretch after eating large meals and help to move and clench the food for easier digestion. The stomach can be separated into four different areas based on function and shape.
1. The Cardia
connects the esophagus and stomach and is a tube like section that separates into the larger areas of the stomach.
2. The Esophageal
sphincter (located inside the cardia) is a band of muscle tissue that tightens to hold the food and acid within the stomach.
3. The Fundus
located at the upper-most part of the stomach. Its purpose is to store and to gather gas (which is a total normal part of digestion) and store any extra food when needed.
4. The Pylorus
connects the stomach to the duodenum and within it is the pyloric sphincter which controls the flow of semi digested food into the duodenum.

6. 5. Small Intestine
The small intestine is a tube roughly 10 feet long and 1 inch in diameter. It is located under the stomach and takes up the most space in the abdominal cavity. It is coiled like a hose and is filled with many ridges and fold that are used for to increase the absorption and digestion of nutrients. By the time food leaves the small intestine 90% of the nutrients has been extracted.
6. Liver & Gallbladder
The liver is a triangular shaped organ on the right of the stomach. Its function to the digestive system is to produce bile and secrete it to the small intestine. The gallbladder is a pear shaped organ just to the back of the liver. Its function is to recycle the bile from the small intestine to reuse it in further digestion of other.

7. 7. Large Intestine
The large intestine is double the size of the small intestine in diameter (2 ½ inches) but half as long (at around 5 feet). It wraps around the small intestine and is responsible to absorb water and break down waste to further extract the nutrients from it from the help of small bacteria. Food ends its journey here in the large intestine going out of the body through the anal canal.

8. Digestive System & Other Systems
Circulatory System
The circulatory system and the digestive system work very closely together to help distribute the absorbed nutrients throughout the body.
Respiratory System
The respiratory system and the digestive system work together to help each function and they both provide energy to body cells throughout the body.

9. Fun Facts
It takes roughly 7 seconds for food to travel trough the esophagus and reach the stomach.
The stomach of an adult can hold up to 1.5 liters of food and the food stays here for 2 to 3 hours.
The estimated surface area of the small intestine is 2,700 feet. (that’s over half the size of a basketball court)
The whole digestive region is over 29 feet long. (starting at the month and ending at the anus)
The stomach wall has 3 layers of muscles.

10. Diseases The Stages of Cancer
Colorectal Cancer
Colon cancer is a very infectious tumor growing on the inner wall of the large intestine. It is the third most common cancer diagnosed in humans and also the second highest cause of deaths due to cancer. But it is still very curable if caught early. Some warning signs of colon cancer could be changes it bowel patterns, weight loss or fatigue but in the early stages of the cancer there are almost no symptoms which makes it that much harder to catch which is why it is so high on the amount of deaths. It is much more common in people above the age of 50 so it is recommended that anyone above this age gets a screening colonoscopy once a year.
The survival rates for Colon Cancer is about 74% for stage one tumors but down to only 6% with stage four tumors.
Colon cancer develops in the digestive track in the body so it becomes painful or hard to eat and digesting becomes difficult.
The Stages of Cancer
Stage Zero- Cancer is found in very little proportion on the innermost lining of the colon or rectum.
Stage One- Cancer in only on the inner wall of the rectum or colon.
Stage Two- Cancer has spread into the muscle layer of the rectum or colon.
Stage Three- Cancer has spread into at least one or more lymph nodes.
Stage Four- Cancer has spread into different parts of the body such as the liver, lungs bones, etc. This is not dependent on the tumor.

11. Diseases Continued Crohn’s Disease
Crohn’s disease is a smaller part of a bigger group of digestive conditions called “Inflammatory Bowel Disease”. (IBD)
It most commonly affects the small intestine called the ileum but can affect any part of your digestive track. This kind of disease attacked its own healthy cells thinking they are invaders which means it is an autoimmune disease.
Some common symptoms are abdominal pain, diarrhea, rectal bleeding, weight loss and fever.
Some treatment options depend on the symptoms you may be showing and could be pain relievers, immunosuppressant's or surgery.

12. Bibliography
9 Common Digestive Conditions From Top to Bottom. (n.d.). Retrieved April 14, 2016, from conditions-from-top-bottom/
15 Fun Facts About the Digestive System - DigestiveSystemforKids.com. (n.d.). Retrieved April 12, 2016, from digestive-system/
Colon Cancer: Symptoms, Signs & Stages. (n.d.). Retrieved April 14, 2016, from
Digestive System. (n.d.). Retrieved April 12, 2016, from
Function of the Digestive System. (n.d.). Retrieved April 12, 2016, from digestive-system/function-of-the-digestive-system\
How Do the Digestive & Respiratory Systems Work Together? (2013). Retrieved April 12, 2016, from digestive-respiratory-systems-work-together/
Taylor, T. (n.d.). Digestive System. Retrieved April 12, 2016, from