Skull, vertebral column and limbs
Head, trunk and limbs are the three parts of our body.
Skull is situated in the Head.Thoracic ribs are seen in the trunk portion.Certain bones are seen in hands and legs.Back bone gives support to all these bony structures.
Brain is the most important part of our body.This is present inside the skull, in a safe position.Two eye cavities and areas for internal parts of the nose and ears also present in the skull.
The skull is made up of 22 large and small bony pieces.Nose and ears are made up of a bony substance.The skull is made up of the bones with immovable joints.Lower jaw is attached to the skull.It can move up and down.Teeth are fixed in the bony jaws.
Chest box (Rib-cage):
Vertebral Column or Back bone gives support to the body.We can remain straight and also bend with the help of vertebral column.
The vertebral Column is made up of thirty three vertebrae.The spinal cord, starting from the brain passes through the canal of Vertebral column.Nerves are given off from the brain and spinal cord.These nerves convey the messages from brain to the body organs to brain.
In the chest or thoracic region, twelve pairs of ribs arise from the back bone.The structure formed by the back bone (vertebral column), ribs and breast bone, looks like a cage.This is called the chest box or Rib-cage or Thoracic cage.Vital organs of our body such as Heart and lungs are protected in this cage.