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Human DigestionScience 7
by: Mr. Rockensies
Aim: How does the digestive system break down food into nutrients?
Do Now: How many feet does your food travel through the digestive system?
HW: Worksheet
The Stormy Sea
“Then, the valve to the stomach opens and pizza mush lands in your stomach!”
“The small intestine looks like a strange underwater world filled with things that resemble small finger-like cactuses.”
“A glorious, if slightly stinky, journey, don't you think?”
Name the term used to describe the muscular contraction that pushes your food down the esophagus and into the stomach.
Describe the role that mucus plays in the stomach.
Determine the 5 steps that food takes as it travels through the digestive system.
In-class Exercises
peristalsis
Acts as a liner, protecting the stomach from acid burns
1)Eat the food2)Food enters stomach and is further digested by
acid3)Nutrients are absorbed by the small intestine4)Waste not absorbed has water taken out by large
intestine5)Waste is removed from the body
Eat/Ingest
In-class Exercises
What is digestion?
EDDiEE
D
Di
E
Diffusion
Digestion Eliminate/ Egest
The breakdown of food so that it can be absorbed
You chew food with your teeth, breaking it down into smaller pieces. Saliva breaks down starch molecules into
simple sugars.
The esophagus pushes the food down to the stomach
using peristalsis. The stomach fills with acid and contracts to
mix the food and acid.
After the stomach, the food enters the small intestine and is mixed with juices filled with
enzymes that further break down food to be absorbed by
villi
Food then travels to the colon, or large intestine, where it is
dehydrated. The water is removed and the remaining waste is then pushed out of
the body by the rectum through the anus
In-class Exercises
How is food broken down?
a) physical changes
b)chemical changes
Food is broken down mechanically – chewing, mixing, grindingEx: Teeth chewing, stomach churning
Food is mixed with acids and digestive juices containing enzymes to further break down food and release nutrients for absorption
1) E - eat/ingest
2) D - digest
3) Di - diffusion
4) E - eliminate/egest
Hypothesize what might happen if H2O was not removed during the final stages of digestion in the large intestine.
Mouth, teeth, salivary glands, tongue, esophagus
In-class Exercise
s
Stomach, pancreas, liver, gall bladder, small intestine
Small intestine (villi), large intestine
Large intestine, rectum, anus