The organ system that generates body heat and provides for locomotion of the body as a whole is the muscular system.

Here's why:

* Heat Generation: Muscle contractions require energy, and a significant portion of that energy is released as heat. This is why we get warmer when we exercise.

* Locomotion: Muscles are responsible for all movement in the body, from walking and running to breathing and digestion. They contract and relax, pulling on bones and other structures to create motion.

While other systems play a role in body temperature regulation (like the circulatory and integumentary systems) and supporting movement (like the skeletal system), the muscular system is the primary driver of both heat generation and locomotion.