We now survey the major systems of the body. The purpose at this stage in the unit is merely to start you off on this journey. It introduces you to ‘what is where’ and provides a basis for study in this unit. Musculoskeletal system: Muscles and bones take a lion’s share of the total weight of the body. The bone is complete largely of bones. Bones form hard; strong supports for the body, in many places protect delicate structures, have joints with various degrees of movement, and also act as a store of calcium in the body. Muscles move the bones at joints, bringing about movement of the whole body or its parts. For this reason muscles and bones are usually grouped together in one system. A look at the image reveals more and piece of the border runs during the centre of the stiff, along and around the long axis of the body. This is the axial skeleton, comprising the skull, vertebral column and the ribs. The limbs are develop as extensions of the trunk and are seen as appendages (attachments) of the trunk. The bones of limbs form the appendicular skeleton. Bones display a variety of form, and can be thought of as long bones, short bones, flat bones and irregular bones.