Limb bud

Definition

A limb bud is an early embryonic structure that develops into the limbs (arms and legs) of an organism, composed of a core of mesenchymal cells covered by ectoderm. It undergoes a complex process of growth and differentiation to form the bones, muscles, and nerves of the appendicular skeleton.

Related terms

Mesenchymal cells: These are multipotent stromal cells that can differentiate into various types of cells, including those that form bones and muscles.

Ectoderm:

The outermost layer of cells or tissue of an embryo in early development that gives rise to the outer body covering and nervous system.

Appendicular skeleton: Comprises the bones of the upper and lower limbs, as well as the pectoral girdle and pelvic girdle, which attach the limbs to the axial skeleton