The Skeleton and Muscles
- The functions of the skeleton are support, protection and movement.
- Muscles are attached to bones. When they contract they alow us to move.
- Bone is made of living cells. and calcium compounds The living part of the bone lays down the non-living part.
- All vertebrates have a spine made up of vertebrae.
- A joint is where 2 bones come together, e.g. the elbow or the knee.
- Fused joints do not allow movement, e.g. the bones of the skull.
- Ball and socket joints allow movement in any direction, eg the shoulder and the pelvis.
- Hinge joints allow movement in one direction only, e.g. the knee.
Ligaments and Tendons
- Ligaments join bone to bone.
- Cartilage acts as a shock absorber between bones.
- Synovial fluid acts as a lubricant.
- Tendons join muscle to bone.
- Antagonistic muscles are pairs of muscles that pull in opposite directions, e.g. the biceps and triceps of the arm.
- To raise the arm, the biceps contracts and the triceps relaxes. To lower the arm, the triceps contracts and the biceps relaxes.