Internet version [Naruhodo no Mori] Vol.41

by Yumiko Mori

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Vol. 41     September 15th, 1998

Holes on bones

Home science experiments for mothers of elementary school children

Mom: "Can you look for holes? Tell me if you find one."
Tae: "Hole?"
Mom: "Yes, it is supposed to be somewhere in the middle, where bones are narrower."
Tae: "Oh, I found it! Is this what you are looking for?"
Mom: "Yes, that's right!"
Satoshi: "Mom, I found one too."
Mom: "Let me see. Oh, this is amazing!"
Mom is amazed at the bone Satoshi has showed her. A red thread is attached to the bone.

Tae: "What is this? Is this possibly a blood vessel?"
Mom: "You guessed right!"
Satoshi: "What is 'blood vessel', Mom?"
Mom: "It is a tube blood passes through. When you get injured, you may bleed. Right?
Your blood flows through in the entire body. It even flows through bones.
Shall we cut this bone and look inside the bone?"
Tae: "OK, I am going to try to break this bone by hand."
Mom: "No way, you can't do that."
Tae is trying hard to break the bone.
Mom: "Well, we need a saw to cut this bone."

Materials

• Chicken meat that still attach to bones
  (Chicken legs or wings)

  

• A small pot
• A glass cup
• A magnifying glass If available
• If you want to cut a bone
  A saw
• If you want to preserve bones
  Hydrogen peroxide

Bone inspection

[Inspection of bone holes]

1. After you finish eating meat, check if holes are on the bones.
2. Remove white colored cartilage from the ends of the bones. Wash the bones very well.
3. Investigate where holes are located on bones, how many holes can be found, and how big holes are.



• If meat remains on your bones, boil them in a plenty of water for 20 minutes.
  After this boiling, meat should come off easily. Rinse bones very well.

• Even though meat is removed from bones, they will stink after a while.
  If you want to preserve bones, dip them in hydrogen peroxide for one day and dry them completely. After this procedure, bones would not smell much, but the color of bones turns to white.

[Experience of Bone Cutting]

1. Try to break a bone by hands.
2. Cut a bone by sawing.



• Cut near the end and at the middle and compare their openings.
  Inspect bone thickness and bone marrow.
• Human bones have holes at similar positions. The number of holes per a bone is various.

• Bones are very strong but lightweight.

• Bone holes for blood vessels are located at the positions where the vessels are not squeezed even if the bones are under tension.

• Spareribs can be used for studying the inside of bones.

   My husband proposed an experiment of making cookies from crushed bones. Such an experiment would give so much strain to my bones. Still crushed bones could be good for me, since I am a middle-aged woman and will need extra calcium. I have heard old bone cells are constantly removed and replaced with new cells. Apparently the entire cells are renewed every 2 years and a half. Even when I am not working, my body is functioning without interruption. Living organisms are all working in order to 'live'.

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