The baby's skeleton is
very different from the adults. The baby is less likely to break his
bone as compared to an adult. This is because the new born has more
than 300 parts, which can be called bones, although some of them
contain very little true bone. They are made of very flexible and
soft cartilage, which bends rather than breaking. Cartilage is a
connective tissue that covers the ends of the joints, acts as spongy
cushion in between vertebrae.
As we grow, bone, replaces the cartilage, some of the separate
bones, fuse together thus reducing the total number of bones to 206
by the age of 20. The skeletal system is made of bones, cartilage
(which at some places plays a structural pole as in nose, ears, and
ribs), and ligaments (stabilizes the skeleton by holding the joints
together).
The bones are of four main variety:
- Long bones
- Long bones are present in the limbs, are longer than wide, and act as levers that make the body move, when pulled by the muscle contractions.
- Short bones-
- The wrist and ankle bones i.e. carpals etc. are cube shaped. Flat bones- ribs, sternum, scapula, etc. work as protective cages, and have big surfaces for muscle attachments.
- Irregular bones-
- Vertebrae, skull bones, pelvic bones, etc.
If steel had to replace the skeleton and have the same strength as bones, it would be 5 times as heavier.
Did you know?-----
X-rays were discovered in 1895.
Bone healing:
The bones heal best and fastest if, the broken ends are brought together in their natural alignment, a process called 'reduction of fracture'. Healing starts almost within an hour of a fracture. The leaking blood from the broken ends forms a clot, cells known as fibroblasts and osteoblasts make a network of soft, spongy bone in the gap, this spongy bone fills in gradually to become hard, and blood vessels re-grow in it. within 2-3 months the excess bone is absorbed by a process called remodeling.