Transcript Essential Question Nutrient molecules pass from the small intestine

Bell Ringer
• What you need for
class:
–
–
–
–
–
Pencil
Science notebook
New bell ringer sheet
Colored pencils
scissors
• The transport tube
that carries chewed
food to the stomach
is the —
a. esophagus.
b. stomach.
c. intestine.
d. mouth.
Bell Ringer
• What you need for class:
–
–
–
–
Pencil
Science notebook
Colored pencils
scissors
nose
trachea
?
lungs
• The organs that move the
air from the trachea to the
lungs are missing in the
diagram above. What are
these organs called?
a. bronchi
b. diaphragm
c. alveoli
d. capillaries
The Digestive
System
SC Indicator 7-3.2
Recall the major organs of the
human body and their functions
within their particular body
system.
SC Indicator 7-3.3
Summarize the
relationships of the major
body systems.
Essential Question
What are the 3 secondary
organs that food does not
actually travel through,
but are very important in
the digestive system?
Essential Question
A wet ball of chewed up
food is called a __.
Essential Question
The flap of tissue that
closes across the windpipe
to keep food from
entering it is called the
___.
Essential Question
What organ
produces bile?
Essential Question
What are the 3 major
functions of the
digestive system?
(3 words)
Essential Question
What substance must
be present in the
stomach for pepsin
to work best?
Essential Question
Nutrient molecules pass
from the small intestine
into the bloodstream
through tiny structures
called ____.
Essential Question
Bile made by the liver is
stored in the ___.
The Human Digestive System
What happens
when I eat
pizza?
What happens when I eat pizza?
• Although it smells really good, in its current
form, that pizza will not do my body much
good.
• It is much too large to squeeze into my tiny
cells.
• Even if I could get it into one of my cells,
that cell would not be able to use it.
• What do I need to do to the pizza before I
put it into my cells?
• That’s right! I need to break it down into
smaller pieces.
I use
my
teeth to
take
that
first
delicious
bite!
Your mouth is the chomping
champ!
• As I lift the slice of pizza up towards my
mouth, what is the first thing I do to
begin breaking it down into smaller pieces?
• That's right, I bite it.
• The pizza slice is too big to swallow in one
giant gulp, so I bite the tip off.
• Already I have begun breaking it down,
haven’t I?
But wait!
• Now what am I doing?
• I am still breaking it down into smaller
pieces.
• I am squishing it, and grinding it, and
cutting it using my teeth.
• Something else very important is also
happening.
Bite the pizza and chew it up!
What else is happening?
• My mouth produces a chemical called
saliva, which is more commonly referred to
as spit.
• Saliva is produced by my salivary glands,
and is released as I begin to chew.
• It can also be released when I smell
something yummy.
• Saliva has a couple of important jobs to
perform.
The Job of Saliva (spit)
• First, it moistens my food.
• This makes it easier to chew and helps
lubricate it so that it can travel through
my body more easily.
• Saliva also contains chemicals that begin
to break my food down into smaller pieces
through the process of chemical digestion.
Saliva moistens
food.
It also contains
chemicals that
start to break
down food right
away in your
mouth.
Teeth cut it,
grind it, and
squish it.
Saliva starts
chemically
breaking down
the food.
How is food broken down?
• Now I am holding a slice of pizza in my
hand with a bite missing out of it.
• In my mouth I have a small wet ball of
mashed up crust, sauce, cheese,
pepperoni, and saliva, called a bolus.
• So what's next?
I’ll swallow it,
of course!
The Esophagus
(The Waterslide of the Body)
• Uh Oh!! Here it comes.
• Wait… I swallow it.
• That wet ball of chewed up pizza begins a
long journey towards the cells of my body.
• At this point it is still much too big to fit
inside any of my tiny cells.
• Even the smallest pieces would be far too
large to do my cells any good.
The Esophagus
(The Waterslide of the Body)
• After swallowing my pizza bite, it enters
into my esophagus.
• The esophagus is like a long slippery
waterslide.
• Muscles within my esophagus squeeze the
food down towards my stomach.
The ESOPHAGUS = Food Tube
Esophagus
Esophagus
The Esophagus
• Whether I am standing
up, laying down or hanging
upside down, I can safely
swallow a bite of food,
because the muscles
within my esophagus know
that their job is to send
food in only one
direction… towards my
stomach.
A Look
Inside
Your
Esophagus
Muscles move
the food down
the esophagus
during
peristalsis.
Peristalsis is
when food is
squeezed by
muscles and
pushed down
to your
stomach.
The Stomach
• As that pizza bite falls into my stomach,
a round muscle called a sphincter closes
behind it.
• This protects the esophagus from having
food or other chemicals splash back into
it.
• The single pizza bite is soon joined by
other bites as I continue eating.
Look at my pizza go…
What is HEARTBURN?
The Stomach
(continued)
• After a few minutes my stomach is
completely full.
• Because I feel full, I stop eating, and run
off to do some household chores.
• As I walk the dog, dust and sweep, run the
vacuum, load the washer and fold the
clothes, I don’t think about the food or what
it is doing inside of me, but my body does
not forget about it.
• Deep within me, my body continues the
process of breaking food down into smaller
and smaller pieces.
The Stomach
(continued)
• For the next couple of hours my stomach
muscles churn and grind the food in my
stomach, causing it to roll over and over
again.
• Glands within my stomach release a variety
of powerful chemicals which help to
further break down the food within me.
Most mechanical
digestion occurs
here.
The stomach
muscles churn
and squeeze it
like clothes in a
washing machine.
The Stomach
(continued)
• The two most important chemicals in my
stomach are hydrochloric acid and pepsin.
• Together these chemicals break the pizza
down into a slush known as chyme.
Digestive juices,
like pepsin and
hydrochloric
acid, help more
chemical
digestion to
occur.
Mucus coats and
protects the
lining of your
stomach.
My Small Intestine
• Although the slushy chyme is much more
broken down than the original pizza bite,
the small pieces floating in the chyme are
still too large to fit inside my cells.
• They must be broken down even further.
My Small Intestine
• Once the chyme is ready, a valve opens in
my stomach and releases the chyme into
my small intestine.
• The small intestine is where most of the
digestion process takes place.
• It’s where most chemical digestion occurs.
My Small Intestine
• As the chyme enters my small intestine it
is mixed with a variety of chemicals,
whose job it is to further break down the
pizza.
• My liver adds a liquid known as bile which
helps to neutralize the acids from my
stomach, so that digestion can continue to
take place.
Food leaves the
stomach and
enters the
small intestine.
As I said, most
chemical
digestion takes
place here.
My Small Intestine
• By now, I am done with all my chores,
have walked the dog again, and I’m sitting
on the sofa watching television.
• The chyme is slowly moving further along
in my small intestine.
• As it moves along, the process of digestion
is almost complete.
• My small intestine is lined with tiny folds
called villi.
Villi in the Small Intestine
• The muscles within my small intestine
squeeze and roll the food about.
• As it sloshes around, the villi quickly
absorb the nutrients from the chyme,
leaving behind the materials that are not
nutritious.
• So…the job of the small intestine is to
absorb the nutrients from the foods we
eat! Remember that.
Villi in the Small Intestine
Villi
in your small
intestine give
more surface
area for
nutrients to
be absorbed.
More surface area means that more
nutrients can be absorbed by your body!
The Large Intestine
• As chyme enters my large intestine, there
are virtually no nutrients left.
• The job of the large intestine is to remove
water from the remaining waste.
• Water is very important to my body, and
it cannot afford to allow water to leave
unnecessarily.
• Slowly the chyme passes through my large
intestine becoming dryer and harder.
The large
intestine
absorbs water
into the
bloodstream.
The remaining
material is
readied for
elimination
from the body.
The large intestine is about 1½ meters
long – about as long as a bathtub.
The End of the Journey!
• Eventually, after about 24 hours, my body
no longer needs what remains of that
pizza.
• It has traveled from my mouth to my
large intestine, getting smaller and more
broken down each step along the way.
• Because all of the nutrients and water
have been removed from the pizza, all
that remains is to get rid of the waste
that has been left behind.
The short tube at the end of the large
intestine is called the rectum.
Waste material is
compressed into solid form
in the rectum
The waste material, or
feces, is eliminated from
the body through the
anus.
The anus is a muscular
opening at the end of the
rectum.
Rectum & Anus
The End of
the
Journey!
The End of the Journey!
The End
of the
Journey!
Let’s Review!
Organs of
the
Digestive
System
Organs
of the
Digestive
System
& Their
Functions
Organs of the Digestive System
& Their Functions
Let’s go
through
these
organs
again…
…and
again…
…and
again.
Cool Picture
Inside the
human
body…organs of
the digestive
system.
Our
Digestive
Tract
The Human
Digestive
System
The Human Digestive System
Salivary
Glands
Mouth
Salivary
Glands
Esophagus
Liver
Large
Intestine
Anus
Stomach
Small
Intestine
Rectum
Digestion Animation
Let’s look on the Internet at an
animated explanation of the
DIGESTIVE SYSTEM!
http://highered.mcgraw-hill.com/sites/0072495855/student_view0/chapter26/animation__organs_of_digestion.html
Digestion Animation
Let’s look on the Internet at an
animated explanation of the
DIGESTIVE SYSTEM!
http://health.howstuffworks.com/human-body/systems/digestive/adam-200142.htm
Label the Digestive
System #1
Let’s see if you can remember
all of the organs of the
digestive system…
http://www.neok12.com/diagram/Digestive-System-01.htm
Label the Digestive
System #2
Let’s see if you can remember
all of the organs of the
digestive system…again!
http://www.neok12.com/diagram/Digestive-System-01.htm
Mouth
Gallbladder
Large
Intestine
Stomach
Pancreas
Small
Intestine
Rectum
Label the
Diagram
Can you
name the
organs of
the
digestive
system?
Cool Demonstration of the
Digestive System
I loved this demonstration…though
some is a little cheesy!
Enjoy it!
http://www.neok12.com/php/watch.php?v=zX4559475700465
170435873&t=Digestive-System
A Trip Through the Digestive
System
Would you like to take a trip
through the digestive system?
Let’s GO!
http://nature.ca/discover/exm/blddgstvsystm/index_e.cfm
The Digestive System
What is the digestive system?
Kid’s Health will help us understand!
http://kidshealth.org/kid/htbw/digestive_system.html
Salivary Gland
Teeth
Throat/Pharynx
Epiglottis
Esophagus
Liver
Gallbladder
Bile Duct/Tube
Stomach
Begin Small Intestine
Pancreas
Large Intestine
Appendix
Small Intestine
Rectum
It’s your turn
to illustrate
the organs of
the digestive
system.