Skeletal muscles mechanically move the body. Messages from the nervous system cause these muscle contractions.
Almost the entire system of an embryo is made of cartilage, whereas that of an adult is mostly made of bones.
Answer:
In physical appearance can be changed by different DNA but for mental not very sure.But mental state can be altered when the DNA has anomaly or mutation. Mostly, people whom has high education always study hard for example students even they have physical problem but they still have good mental
