THE DIGESTIVE SYSTEM

Presented by Tyler Beaulieu, Morgan Ferguson, Gavin Kearney, Robert Pike, and Brandon Yuettner

The Digestive System The digestive system breaks down

foods and makes them into useful forms and it all goes through the mechanical and chemical digestion. Mechanical, physically breaks foods up such as by chewing. The smaller pieces are acted upon by digestive enzymes. Digestive enzymes change complex molecules into much smaller molecules that the body can easily utilize. This process involving enzymes is called chemical digestion.

Mouth

The starting point of the digestive system is the mouth. Incisors the teeth in the front cut and slice the foods. Molars the teeth on the sides of the mouth mash and blend the foods with saliva. The tongue than shapes the food-saliva mixture in to a ball known as the bolus. After it than pushes the bolus into the pharynx.

Stomach

When the tongue shapes the bolus it then pushes the bolus down the pharynx. The bolus then enters the stomach and it stays there for up to six hours. The bolus is churned into small pieces and mixed with gastric juice. It than changes the bolus into a liquid the bolus will now be called chyme.

THE GALLBLADDER

Gallbladder is small storage organ located next to the liver. The gallbladder plays an important role for digesting food. The gallbladder holds bile which is needed for digesting fatty foods. Sometimes the bile will crystalize and cause gallstones. The gallbladder is only three inches long and 1.5 inches wide.

Liver

The right lobe of the liver is the largest of the two lobes by six times. The liver itself weighs 3 pounds in the body. The liver performs many essential functions related to digestion, metabolism, and immunity within the body. The liver also helps the body use carbohydrates, another important component in food.

SMALL INTESTINE A S M A L L I N T E S T I N E I S A L O N G T U B E T H A T ’ S A B O U T 1 ½ I N C H E S T O 2 I N C H E S . T H E S M A L L I N T E S T I N E B R E A K S D O W N T H E F O O D M I X T U R E E V E N M O R E S O Y O U R B O D Y C A N A B S O R B A L L T H E V I T A M I N S , M I N E R A L S , P R O T E I N S , C A R B O H Y D R A T E S , A N D F A T. T H E S M A L L I N T E S T I N E I S D I V I D E D I N T O T H R E E S E C T I O N S ; T H E J E J U N U M ( W H E R E A L L T H E N U T R I E N T S A R E A B S O R B E D ) , T H E D U O D E N U M ( T H E R E C E I V I N G A R E A F O R C H E M I C A L S ) A N D T H E I L E U M ( W H E R E T H E R E M A I N I N G N U T R I E N T S A R E A B S O R B E D B E F O R E M O V I N G I N T O T H E L A R G E I N T E S T I N E ) .

Large Intestine

The large intestine takes care of absorbing water that hasn’t been digested yet. It passes any unused waste from the body. The large intestine is 4.9 feet length.

The large intestine absorbs important vitamins and stores feces. The large intestine is found in the pelvis area where it is attached to the smaller intestine.

Dear Medulla Oblongata,

The digestive system has many functions. The starting point of

the digestive system is the mouth. The incisors, teeth in front of the

mouth, cut and slice the food while the molars, teeth towards the back of

the mouth, mash and blend food which mixes with the saliva. For

example, if we couldn’t chew our food, the food would be too big to

swallow and we would choke. Next we have the stomach. Our stomachs

are able to hold food for up to six hours. The reason for this is if we

weren’t able to hold food in our stomachs then we would have to eat all

day long. Now on to the gallbladder. The gallbladder holds bile which is

needed to digest fatty foods. Matter of fact, if you didn’t have a

gallbladder chances are you could be overweight.

In addition to the gallbladder, we also have the liver. The liver breaks

down toxins. Toxins are harmful to the body. Such toxins include

drugs and alcohol. As a result, not having a liver would be very fatal to

the human body. Equally important is the small intestine. The small

intestine absorbs 90% of what we eat giving us all the nutrients we

need to survive. In fact, if the small intestine did not function

correctly we would not have the nutrients we need to survive. Finally

we have the large intestine which passes any unused waste from the

body. Waste is something that the body has taken all nutrients from

and does not need anymore. In conclusion, the digestive system has

many functions.

Sincerely,

Tyler, Robert, Gavin, Brandon, Morgan

Bibliography Manolis Kay, The Digestive System. Minneapolis, MN, Bellwether Media, Inc., 2009 Royston Angela, Eating and Digestion. Chicago, Illinois, Rigby Interactive Library, 1997  Parker Steve, Digestion. Chicago, Illinois, Raintree, 2004