simply said, bones consist of 2 thinges: cork-like stuff, and chalk-like stuff. chalk makes it hard
Bone hardening is when you build up the bones mainly in your legs and arms by creating small fractures in the bone that, when healed, is harder and thicker than before.
simple answer: calcium being deposited in the bone stable pool
hydroxyapatite
calcium vitamin D and a lot of exercise
arm
Because children have more bones than adults. They is because the bones fuse together when the children are growing. A baby has 300 bones at birth. But because bones fuse together during the "growth period", adults have less bones and they end up with 206 bones.
Children are more flexible in general because compared to developed adults they are still growing and attaining calcium as well as other vitamins that help harden bones and make them inflexible.
Bone starts as cartilage in the fetus. As the fetus takes on the final shape, this cartilage arranges, and enough hardening occurs in the limbs to allow the creature to stand shortly after birth. At that point, all the bones begin to harden, and continues to harden all throughout life. Bones contain a level of cartilage all the way until old age.
Nutrients and calcium can make bones tough.
Bones can harden if you drink calcium.
arm
permineralization
the flame ops us a wtare to make it harden
A reduction in temperature.
Calcium from milk makes our bones
Answer
leaving it out in the cold or puting it in a freezer
Your parents make you, so your parents makes bones.
'''Calcium''' makes milk healthy for our bones.
They contain a substance called hardener.
Minerals like calcium and phosphorus :)