Instead of a internal skeleton a scorpion has a exoskeleton that protects its vital organs and muscles. Inside the exoskeleton is over 150 pairs of muscles The most obvious body muscles are the dorsoventral muscles. These attach to a tergum dorsally and to a sternum ventrally within the same segment. The mesosomal dorsoventral muscles function as compressors and serve a vascular function in regulating abdominal blood pressures.