Gastrulation in frog?

Gastrulation is a critical process in the early development of an embryo, where the single-layered blastula is transformed into a three-layered structure called the gastrula. In frogs, gastrulation occurs during the early stages of embryonic development.

The process of gastrulation in frogs begins with the formation of a small invagination called the blastopore on the dorsal side of the blastula. The blastopore eventually elongates and moves towards the animal pole, creating a groove-like structure called the dorsal lip of the blastopore.

As gastrulation progresses, cells from the dorsal lip of the blastopore migrate inward through the blastopore and move towards the vegetal pole. This movement is known as involution. The cells that invaginate through the blastopore form the endoderm, which will give rise to the innermost layer of tissues in the developing frog.

Simultaneously, cells from the animal pole spread out and move over the surface of the blastula, eventually covering the endoderm. These cells form the ectoderm, which will give rise to the outermost layer of tissues in the frog.

Between the endoderm and ectoderm, a middle layer of cells called the mesoderm is formed. The mesoderm is derived from cells that migrate through the blastopore and then spread out between the endoderm and ectoderm.

Overall, gastrulation in frogs leads to the formation of the three germ layers - endoderm, mesoderm, and ectoderm - which will give rise to the various tissues and organs in the developing frog embryo.