The Digestive System

What happens to the food you eat once you

swallow it???

Our Bodies NEED food!

• Our body doesn’t tell us to eat just because it is hungry.

• Our bodies need the nutrients that are inside the food we eat.

• Some examples of good nutrients are proteins, vitamins, and minerals.

Food follows a path through our body!

•Food enters your body through your mouth.

•Digestion begins as soon as food is placed in our mouth.

We have several Salivary Glands

• The pink pictures show our salivary glands

Diagram courtesy of AllRefer.com Health

Digestion Begins:• Digestion begins when these enzymes in

your saliva start to break away at the food you are eating.

• Your teeth continue to help the digestion process as they grind up the food.

• Your tongue also helps digestion when it pushes your food around so it can be broken down.

It all starts here!!

TEETH

TONGUE

SALIVARY GLANDS

Diagram courtesy of 3Dscience.com

Then you swallow •The food you swallow goes down your esophagus, which is the tube that takes it from your mouth into your stomach.

•Peristalsis is the squeezing action in your esophagus that pushes the food down!

Your Epiglottis

Diagram courtesy of AllRefer.com Health

•A flap called the epiglottis closes over the trachea so food doesn’t go into your lungs and choke you! Instead food goes down the esophagus!

Now it’s in your Stomach• Once food is in your stomach it will stay

there for 3-4 hours so it can be broken down even more!

• Stomach acids mix with the food and turn it from chunks that we could recognize into a thick paste called chyme.

• It doesn’t even look like food bits once it’s turned into chyme.

Inside your Stomach• While the food is in your stomach

muscles churn the food.• The food bits are also mixed with

enzymes and acids that are made in the stomach wall and shot into your stomach to help break down the food even more.

• After 3-4 hours food bits now look like a thick paste – do you remember what it’s called?

• CHYME!!

Here’s how they look!

The Next Step•Once chyme is made it is passed into the first part of the small intestine called the duodenum.

•It is here where more juices are added to the chyme to help continue the digestive process.

The Liver and Gall Bladder•The Liver makes bile which is a green juice that helps with digestion.

•The Gall Bladder stores the bile the liver makes until it is needed and shot into the duodenum.

The Pancreas•The Pancreas also makes juices that will help break down the chyme.

•The Pancreas makes pancreatic juices.

•These are also shot into the duodenum to help with the digestive process.

Continuing on…• Food, or chyme, does NOT enter the

liver, gall bladder or the pancreas, but instead these organs just make juices that help with digestion in the duodenum!

• The digested material now continues from the duodenum throughout the longest part of the Digestive System, the small intestine.

The Small Intestine•The small intestine can be 18-23

feet long!•The small intestine is where the

nutrients pass into the blood stream so that the plasma can take it to our body’s cells.

•Small finger-like projections called villi grab at the nutrients and pass them into our blood stream.

Villi in the Small Intestine• Here’s what they look like!!

• These are what take the nutrients out of the digested material in the small intestine and into the plasma of our blood

Moving Right Along•As the digested material moves through the small intestine the nutrients are removed leaving only the unwanted, unused material

•This part of the process can take from 8 to 12 hours

Next Stop•Once the digested material is

through the small intestine it is moved into the large intestine.

•The large intestine gets it’s name because it is bigger around than the small intestine.

•The large intestine is only about 5 feet long. Do you remember how long the small intestine was?

•18-23 feet!

The Large Intestine•The Large Intestine takes

whatever liquid is left, out of the material, leaving a more solid matter.

•This is all of the waste material from the foods we eat that our body can’t use.

•What goes in must come out

Some maturity is needed here!!

•The last step of the Digestive Process is to release this waste from our body.

•The solid waste is removed through the rectum and then the anus.

•Digestion is complete!

THE APPENDIX•Have you ever heard of

someone having their appendix taken out? Have you?

•The APPENDIX is a small attachement that hangs off the LARGE INTESTINE.

•There is NO known use for the APPENDIX in our body!

Let’s see it!LIVERESOPHAGUS

STOMACH

GALL BLADDER

LARGE INTESTINE

PANCREAS

SMALL INTESTINE

RECTUMAPPENDIX

Diagram courtesy of 3Dscience.com

Do you remember what each organ does during Digestion?

LIVER ESOPHAGUS

STOMACHGALL BLADDER

LARGE INTESTINE

PANCREAS

SMALL INTESTINE

RECTUM

APPENDIX

Diagram courtesy of 3Dscience.com

Makes bile

Stores bile

Takes out liquid from the digested material

NO known function

Takes food from mouth to stomach

Churns food for 3-4 hours to change to chyme

Makes pancreatic juices

Releases waste

Longest part of digestion – nutrients leave while here and enter blood stream

DUODENUMFirst part of small intestine

The Digestive Path of Food–Let’s write it out!

• Mouth• Esophagus• Stomach• Duodenum/ Small Intestine• Large Intestine• Rectum/Anus• Does food ever go in the liver, gall

bladder, or pancreas?• NO!!!!!!!

So where do the liver, gall bladder and pancreas fit in?

• Mouth• Esophagus• Stomach• Gall bladder and Pancreas shoot juices

into the:• Duodenum • Small Intestine• Large Intestine• Rectum/Anus

Here’s another look:

Large Intestine

Small Intestine

Large Intestine

Small Intestine

Diagram courtesy of UKhealthcare.com

THE END!!

• TELL YOUR NEIGHBOR 3 THINGS YOU LEARNED.

• NAME THE 3 ORGANS THAT HELP WITH DIGESTION EVEN THOUGH FOOD NEVER GOES IN THEM.

• WHAT IS THE ORGAN THAT DOES NOT HAVE A FUNCTION IN OUR BODY?

• WHAT IS FOOD CALLED AFTER IT’S BEEN CHURNED IN THE STOMACH?