Give reason:

a. The movement of animals is based on their skeletal system.

b. Exercise or physical activity is one of the essential requirements for long life.

a. Skeletal system provides the structure & protection for animals. It is made up of bones, ligaments, tendons, joints and connective tissues. The movement of animals depends on different kinds of joints present in the body. It provides a framework for muscles which are attached to the bones. When the muscles contract they pull on the bones of the skeleton, which act like levers to create movement.

b. Exercise or physical activity helps in staying fit & healthy. Through exercise, extra calories burn from our body. Moreover, it strengthens our heart and lungs. It controls our weight which helps in proper movement of our bones. Oxygen levels increases in our blood stream through exercise and thus increasing our lifespan.