Bones are hard because they must have the mechanical strength to support the weight of the animal (or the required proportion thereof, like in a whale) and facilitate the movement of that animal. Imagine trying to stand up if your leg bones were made of soft rubber. You couldn't. And could you reach across the table to pick up a glass of milk if your arm bones were made of that same soft rubber? Nope. Not happenin'.
They are hard because they contain a large proportion of calcium and phosphorus. In addition of providing leverage for movement (as noted above), they also protect parts of the body, like the brain, spinal cord, lungs, heart, and other internal organs. They also store minerals and make blood.
Bone cells and skin cells have different functions.
All bones are light, marrow bones are soft and compact bones are hard.
the outer portionof most bones is a layer of hard compactbone called the "Cortex".
Bones are made up of calcium, phsophorus, sodium, protein, callagen and other minerals so yes sodium is needed to make bones hard.
Calcium
Ossification
soft you can bend and hard you can not
Seal's bones are hard.
All bones are light, marrow bones are soft and compact bones are hard.
Spiders do not have bones. They have exoskeletons which is a hard outer shell.
Hard.
Yes bones are as hard as rock they can take up to 1,000 pounds of pressure
Bones have a hard coating to protect the nerves, marrow and blood vessels located in the cavity,
No insect have bones. They have a hard outer covering, but no bones.
Hard enough to crush your bones
Yes.
Mineral salts from calcium and phosphorus compounds are essential for making bones hard and strong. calcium is the most essential mineral to make bones strong but not all bones are as hard as you think some bones are "Spongy" but we just dont notice it. hope this helps if you need to know this....
in human body they are hard supporting structures called bones