The functions of the skeleton, the classification of bones, the major bones, the classification of joints and the movements they allow, and the role of ligaments and tendons.

What this dot point is asking

Edexcel wants you to state the functions of the skeleton, classify bones, name the major bones, classify the synovial joints, state the movements each joint allows, and explain the role of ligaments and tendons, all applied to sport.

The functions of the skeleton

Classification of bones

The major bones Edexcel expects you to locate include the cranium, clavicle, scapula, the five regions of the vertebral column (cervical, thoracic, lumbar, sacrum, coccyx), the ribs and sternum, the humerus, radius and ulna in the arm, the pelvis, femur and patella, and the tibia and fibula in the leg. Knowing the bone lets you describe a movement precisely, for example the femur acting as a long-bone lever during a kick.

Classification of joints

The movements at joints

The movement possibilities depend on the joint type. Flexion decreases the angle at a joint (bending the elbow in a biceps curl); extension increases it (straightening the elbow in a throw). Abduction moves a limb away from the midline (raising the arm sideways), and adduction brings it back. Rotation turns a bone about its axis (a tennis serve), and circumduction is a circular movement combining the others (the windmill arm of a bowler). At the ankle, plantar-flexion points the toes (a footballer striking the ball) and dorsi-flexion pulls them up (the landing phase of a jump). Matching the movement to the joint that can make it is the skill the exam rewards.

Ligaments and tendons

Because ligaments stabilise joints, they are commonly injured when a joint is forced beyond its range, which is why a sprained ankle (overstretched ligament) is one of the most frequent injuries in sport. Strong ligaments and tendons, developed through training, let an athlete change direction at speed with less injury risk.