Development of Liver, Heart, flexor and limb buds
Liver and Heart
The liver and heart are the largest structures in the early embryo and form a distinctive bulge that can be seen externally.
Flexures
A series of three differential growth centers develop that result in several flexures along the axis of the embryo soon after the branchial arches begin to form. These flexures transform the embryos from a linear structure to ‘C’ shaped structure.
The first flexure occurs in the area of midbrain, the second flexure occurs in the future neck region and the final flexure occurs in the tail region.
Limb buds
Limb buds also appear at an early stage, which are the primordial for the future limbs. These are the mesodermal outgrowths from the body that are covered by the ectoderm of the region.
The limbs are outgrowths from somatopleure. Fore limb bud forms very early in development. After some time, the hind limb bud and tail bud form.
