Our Digestive System- pt. 2

schematic from the web

schematic drawn by the students

Verse:
Surely you desire truth in the inner parts; you teach me wisdom in the inmost place. Psalm 51:6

Book:
"What Happens to a Hamburger?" by Paul Showers

In class we learned that ...

• we don't have to get grossed out by our intestines
• our digestive system is pretty much one very large tube from our mouth down past our large intestine
  
• we have sphincters around the stomach to control flow
  
• the adult small intestine (SI) is about 2" in diameter and about 21' long
• the intestines have to be really smushed up in order to fit inside our body
  
• the fats and proteins in the chyme is further digested in the SI with the help of pancreas, liver and gall bladder
• vitamins, minerals, proteins, carbohydrates and fats are absorbed extensively in the SI
• food can stay in the SI for more than 4h to help facilitate the absorption process
• the inner surface of the SI is lined with finger-like projections (microvilli) to enhance the absorption process
• the nutrients are absorbed from the SI by lymph and blood vessels that look like more chicken feet
• eventually the blood will carry these nutrients to areas in our body of need
  
• the large intestine is about 3-4" in diameter and about 5' in length
• extra nutrients and water is absorbed in the large intestine
• another word for "poop" is feces or stool

Vocabulary words:

• intestines
• absorption
• sphincters
• pancreas
• liver
• gall bladder
• chyme
• microvilli
• feces

Videos:
The server was too slow so we didn't watch these videos
Digestive System - Video 1
The Stages of Digestion - Video 2

Helpful Website:
Kidshealth

Activities to do at home:

To visually demonstrate how
1) the food is pushed through the intestines in a pulsatile motion
2) the nutrients and water are absorbed through the microvilli
3) undigested waste is noticeably less than the starting material

• Take some old porous nylon stockings and cut off one leg, leaving an opening at each end.
• Cook some instant oatmeal, about 2-3 cups and cool.
• Cover the area - things can get a bit messy.
• Pack the oatmeal into one end and gently squeeze the oatmeal from one end to the other end.
• The porous hose will allow nutrients to escape and by the time you've reached the other end, only noticeably smaller amount should be left to be dumped out.