The yolk plug of a gastrula represents which part in the later stage of development?

The concept that the organiser is essential for embryonic development was given by,or for the 'Theory of organiser',the Nobel Prize was given to:

During gastrulation,the dorsal lip of the blastopore (the first external sign of gastrulation) appears:

Development of sexual reproductive organs in the larval condition is known as:

The correct sequence in the embryonic development of a frog is:

The blastopore develops into the future