Anatomical terminology. The somites (outdated term: primitive segments) are a set of bilaterally paired blocks of paraxial mesoderm that form in the embryonic stage of somitogenesis, along the head-to-tail axis in segmented animals.

What is somite in embryo?

Somites are blocks of mesoderm that are located on either side of the neural tube in the developing vertebrate embryo. ... The first pair of somites forms in the anterior part of the trunk, adjacent to the notochord; the remainder then follow, budding off the mesoderm sequentially, from head to tail.

What is a somite?

somite, in embryology, one of a longitudinal series of blocklike segments into which the mesoderm, the middle layer of tissue, on either side of the embryonic spine becomes divided. Collectively, the somites constitute the vertebral plate.