Answer:
Anabolic steroid, also called anabolic-androgenic steroid, drug that mimics the male hormone testosterone in its ability to increase the growth of muscle tissue and in its promotion of male secondary sex characteristics. ... The drugs are also used in veterinary medicine (e.g., to aid recovery from starvation or injury).
Bones are classified by their ability to maintain the actions within a human's body. This is so because a leg for an example, is classified as a "running" ideal bone, etc. along with the rest of the bones.