True
Bones soften sometimes not all the time.
You soak them in cool water.
piezoelectricity
Weightlessness causes the bones to soften and muscle mass to reduce.
Osteoporosis is a condition that causes bones to be weak and brittle.
Because they are not yet joined at birth, the skull is able to deform to be narrower as it passes through the birth canal. If it did not deform, birth would be even more hazardous for mothers - probably fatally ripping them apart!
It is important to wear the right size shoes, because other wise if you don't your bones in your feet will deform.
fluoride is harmful to your health because in can soften your bones and make them more able to be broken
Bones are made up of calcium, phsophorus, sodium, protein, callagen and other minerals so yes sodium is needed to make bones hard.
Osteoporosis is a medical condition of the bones. It is a condition in which the bones become brittle and likely to fracture.
The averege human bones are not brittle, unless you have a condition of some sort.
Disease condition in Joints and Bones