Final answer:
Somites are mesoderm-derived structures that form various connective tissues in vertebrates, including skeletal elements like vertebrae and ribs, the dermis, and skeletal muscles.
Step-by-step explanation:
Somites, which are derived from the mesoderm, play a critical role in the development of various connective tissues in vertebrates. Located on either side of the vertebrate neural tube, the mesoderm undergoes spatial reorganization to form these segmented structures. During embryonic development, the somites give rise to essential parts of the skeletal system, such as the vertebrae and ribs, as well as contribute to the formation of the dermis, and the muscular system, including the skeletal muscles of the back, the body wall, and the limbs. In addition, the mesoderm forms the notochord, a central structure crucial for the animal body's axis formation.