Support, Muscles and Locomotion

Abstract

• 1. A contractile tissue (muscle) acting upon

• 2. a rigid skeleton, which in turn acts upon

• 3. a resisting medium (earth when walking, water when swimming).

• (a) Functions of the Skeleton

• 1. To support the body. (The surrounding air offers no support.)

• 2. Protection — a bony box (cranium) surrounds the brain; the rib cage surrounds the heart and the lungs; the vertebral column surrounds the spinal cord.

• 3. Locomotion — the action of muscles on bones to move the limbs. The bones are jointed, to give a lever action.

• 4. Non-structural functions: (a) production of red blood corpuscles and white blood cells; (b) a reserve of calcium and phosphorus.