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
SALIVARY
GLANDS
TONGUE
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!
LIVER
Let’s see it!
ESOPHAGUS
STOMACH
GALL
BLADDER
PANCREAS
LARGE
INTESTINE
SMALL
INTESTINE
RECTUM
APPENDIX
Diagram courtesy of
3Dscience.com
Do you remember what each
organ does during Digestion?
ESOPHAGUS
Takes food from
mouth to stomach
LIVER
Makes bile
GALL
BLADDER
Stores bile
STOMACH
Churns food for
3-4 hours to
change to chyme
DUODENUM
First part of
small intestine
PANCREAS
Makes
pancreatic juices
SMALL
INTESTINE
Longest part of
digestion – nutrients
leave while here and
enter blood stream
LARGE
INTESTINE
Takes out liquid
from the digested
material
APPENDIX
NO known
function
RECTUM
Releases waste
Diagram courtesy of
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?