Transcript The Digestive System Nicky and Gigi

The Digestive System
BY: NICKY AND GIGI
Food
 The digestive system starts when you take a bite of food. The minute
you swallow a bite of food, the digestive system starts. Why do you even
eat food? You eat food to feed the trillions of living cells that make up
your body. Different cells do different things to keep your body alive
and working. Just like any time you work, your cells get hungry. The
kind of food cells require are energy and raw materials for building.
Cells get this energy and raw materials from three groups of nutrients
called fats, carbohydrates, and proteins. The process of breaking your
own food into nutrients for your cells is called digestion. Pretend you
just ate an apple. Once you swallow a bite of it, your apple goes through
the digestive system. Let’s follow it!
The Esophagus
Your apple is no longer that juicy red apple. In fact, it isn’t really an apple
at all. It is a mashed up wad of food called a bolus. The bolus leaves
your mouth and heads down the esophagus. Muscles along the
esophagus contract to push the bolus along the esophagus. The bolus is
headed towards the stomach.
The Stomach
Once inside the stomach, digestive juices, including acid, are added to the
food. Muscles inside your stomach squeeze and mash the food. The
food changes into a gross, runny liquid. Yuck!
The Small Intestine
After being in the stomach, the food goes into the small intestine. The
small intestine can be 6 meters(20 feet) long. Even more digestive
juices are added to the food. At the small intestine, the food changes
into nutrients that cells need. The small intestine is lined with millions
of capillaries, which are small blood vessels. Nutrients flow through the
sides of the small intestine and into the capillaries. After that, the blood
which is now nutrient-rich, flows through your body. It provides food
for cells.
Undigested Leftovers
 The undigested leftovers of food enter the large intestine and colon. At
this stage in the digestive system, the nutrients have left the food and
fed the cells. The bacteria that lives in the colon breaks down the
remaining food that is still able to be used. Water is taken out of the
food. The remaining stuff is made up of fiber, indigestible material, and
dead bacteria. This is called feces. This material can then exit the body
through the anus.
Cleaning Blood
Food is still not finished with the breakdown process. Remember that still
usable food? Well, that needs to get broken up. At this stage, all that is left
are waste chemicals. Waste chemicals, bits of salts, acids, and dead cells
all end up in your blood flow. This stuff needs to get out of your blood and
your kidneys are the perfect blood cleaners! Kidneys are next to your back
bone and right below your ribs. Your kidneys clean your blood 20 to 25
times a day. They separate cellular wastes from the blood. The salts,
acids, dead cells, and waste materials are taken away from the blood and
converted to urine. Then, they are stored in a tube in the bladder.
The bladder and kidneys make up the excretory system.
Kidneys
In the previous slide, you learned how kidneys help clean blood. But why
do people need kidneys? People need kidneys to keep your blood clean.
If you didn’t have kidneys, waste would be added to your blood and
eventually your blood would be so full of waste that it couldn’t do its
job. You would die. How do kidneys work? Kidneys act as filters that
separate cellular wastes from blood. They also keep a balance between
salts, fluids, and more in your body. Kidneys come in sets of two.