Download The Skeleton and Movement

The Skeleton and Movement
Chapter 8
The 3 functions
of the skeleton
are:
 Support
 Protection
 Movement
The bones of the
arm are:
• Humerus
• Radius
• Ulna
The bones of the
leg are:
• Femur
• Tibia
• Fibula
The Spine
• The spine is made up
of bones called
vertebrae.
• Discs of cartilage
found between the
vertebrae act as shock
absorbers and allow
limited movement.
Joints
• Joints are formed where bones meet.
• Fused joints-These are immovable or fixed
joints (e.g. bones of the skull).
• Moveable Joints contain synovial fluid and
are called synovial joints.
Synovial joints.
• Synovial joints
contain synovial
fluid which
cushions and
lubricates the
joint
• Cartilage-stops
bones rubbing
off each other.
Examples of moveable joints.
Examples of moveable joints are:
• Ball and socket joint-allow movement in all
directions (e.g. Hip and shoulder).
• Hinge Joint- allows movement in one
direction only (e.g. Knee and Elbow).
Ligaments and Tendons
• Tendons join
muscle to bone. E.g.
Achilles tendon.
• Ligaments-join
bone to bone.
Antagonistic muscles
Antagonistic muscles work in
opposite ways to each other (e.g.
bicep and triceps muscles).
• When the biceps contracts, the
arm is raised.
• To lower the arm, the triceps
contracts and the biceps relax.