Hardest structure in the body.
Made of water, inorganic (non-living) material e.g. calcium, phosphorous and organic (living) material e.g. cells that form bones = osteoblasts.
Protects underlying structures.
Gives shape to the body.
Provides attachment point for muscles allowing movement.
Bones are made of two main sorts of bone tissue that vary according to size and function:-
- Compact: solid structure with no apparent visible spaces = strong, hardwearing. It is supplied with blood, lymph vessels and nerves.
- Cancellous (spongy): many spaces containing red and yellow bone marrow. Red bone marrow produces new red blood cells. Yellow marrow stores fat cells.
Skeleton has average of 206 bones.
Strong framework: support softer tissues, maintain body shape and anchors internal organs in position
Muscles attached to bones contract and relax to produce movement.
Organs are surrounded by protective cage of bone.
Blood cells are made inside bone marrow within the bones.
Bones have different shapes according to function: flat, short, irregular, long and sesamoid.
Connected to each other by connective tissue (structural tissue that supports, surrounds and links parts of the body.)