Cells in an embryo’s _______________ will later form muscle, bones, and the circulatory system.

The cells in an embryo’s mesoderm will later form muscle, bones, and the circulatory system.

The mesoderm is one of the three primary germ layers that form during embryonic development, the other two being the ectoderm and endoderm. During gastrulation, mesodermal cells migrate and differentiate into various tissues. Specifically, the mesoderm gives rise to several important structures in the body: it forms skeletal muscle, smooth muscle, and cardiac muscle, contributing to the muscular system. Additionally, it develops into the bones or the skeletal system through a process called ossification. Moreover, the mesoderm plays a crucial role in forming the circulatory system, including the heart, blood vessels, and blood itself. This vital germ layer thus establishes foundations for many system formations in the developing embryo.