Studies on the oogonial cycle in Puntius ticto (Ham.) II. Formation of mature follicles.

During the formation of maturing oocyte and mature follicle most of the changes are observed in the ooplasm while nucleus gets reduced in size and finally vanishes in the ooplasm. Few of the nuclei migrate into the ooplasm (yolk nucleus) which is responsible for the yolk accumulation. The mature follicle is covered by the theca, granulosa and zona rediata.