Eventually, the limb bud develops into bones, tendons, muscles and joints.

Patterning along the limb bud requires signals from many sources.

We tested this by grafting the tip of a limb bud to the flank of the embryo.

By the sixth week, limb buds had appeared.

Within the limb bud, expression also varies as a function of the position along the anterior-posterior axis.

Determines where limb buds will form, and what limbs will develop there.

The limb bud is a structure formed early in limb development.

All limb buds must rely on other signaling factors to obtain their identity.

The eyes and limb buds also are forming.

Cell division is seen throughout the limb bud.