v The Skeletal System is composed of
bones and tissues
The substance that forms the skeleton of the body. It is composed chiefly of
calcium phosphate and calcium carbonate. It also serves as a storage area for
calcium, playing a large role in calcium balance in the blood.
A group or layer of similarly specialized cells that together perform certain
Connects bones to other bones
Attatches muscles to bones.
Joints support movement.
Protects the bones, and acts as a cushion between the bones and joints.
v The Skeleton can be divided into
Ø The Axial Skeleton
of the bones in the head, trunk, and vertebrae. 80 bones
Ø The Appendicular Skeleton
Composed of the shoulder girdle, the
pelvic girdle, and the bones in the arms and legs. 126 bones.
v The Skeleton has six major
It is the framework that supports and maintains the shape of the body.
Joints, which are in between bones, allow for movement e.g. ball and socket
The skeleton protects our organs from damage e.g. the skull protects the brain
and eyes, ribs protect the lungs and heart, the vertebrae protect the spinal
Ø Blood Cell Production:
The development of bleed cells, Haematopoiesis, happens in the skeleton.
Calcium is stored in the bone matrix, and also bone marrow can store iron and
v Bone Composition
Ø Compact Bone: Dense
bone e.g. the long bones in the arms and legs.
Ø Spongy Bone:
Honeycomb-like, flexible e.g. ribs, skull, vertebrae
Ø Bone Marrow:
Soft blood-forming tissue that fills cavities of bones, and contains fat and
immature, as well as mature blood cells.
v Bone Shapes:
Ø Long Bones: Hard,
dense bones that provide strength, structure, and mobility e.g. arms, legs, and
As wide as they are long. Provides support and stability e.g.wrist and ankles
Expanded into broad flat plates. Provides extensive protection e.g. skull and
Various functions in the body such as, protection of nervous tissue tongue
attachment. e.g. Spine