Standard 2c - Students know the sequential steps of digestion and the roles of teeth
and the mouth, esophagus, stomach, small intestine, large intestine, and colon
in the function of the digestive system.
1. Circulatory System Review
Last week you learned
what your blood does in your body.
deliver oxygen to every part of your body?
Platelets White Blood Cells Red Blood Cells
In which body
part does your blood pick up oxygen?
Heart Lungs Arteries
2. The Digestive System
You know that
a car needs fuel to make it run, your body is like a car because
it needs fuel too. Your fuel is food. Your body
makes chemical changes to the food so that it turns into energy
for you. Just how does that happen?
swallow a whole apple? No way, it won't fit! You have to
make it smaller so that it will fit into your mouth. How do you do
teeth are like little chopping machines. They chop and grind your
food into little pieces so that they can be swallowed. Saliva makes
it mushy so that it's easier to swallow. Where does it
mouth is part of your head, and your stomach is in the middle of your
body. So how does food get from your mouth all the way down to
esophagus is a tube about 10 inches long that connects your mouth to
your stomach. The esophagus has muscles that squeeze the
food, like when you squeeze toothpaste out of the tube. It moves
the food slowly into the stomach.
Did you know that food
spends 2 or 3 hours in your stomach? It doesn't just sit there, your
stomach is busy mixing the chunks of food you swallowed with acids that
turn it into a milkshake like mixture.
6. Small Intestine
your stomach is done making a mushy milkshake like mixture of your food, it goes to the
small intestine. The
small intestine has the important job of breaking down the food mixture
so your body can absorb all the nutrients it needs from food - vitamins,
minerals, proteins, carbohydrates, and fats.
Your small intestine is 22 feet long!
7. Large Intestine
that cannot be absorbed into your body goes to the final part of the
journey, the large intestine. The large intestine is fatter than
the small intestine and its job is to move all the things your body
doesn't need out of your body. It holds all the waste until you
are ready to go to the bathroom.