Question

In the development of a frog embryo, Which of the following would be the speman's primary organizer?

• A. Dorsal ectoderm
• B. Dorsal lip of the blastopore
• C. Archenteron
• D. Neural tube
• E. Notochord

Answer 1

The correct option is B Dorsal lip of the blastopore

Embryogenesis is the process by which an embryo is formed and developed.
This process starts with the fertilization of the egg cell by the sperm cell and once fertilized, a diploid cell zygote is formed. The zygote further undergoes mitotic divisions or cleavages and cellular differentiation which develops into a multicellular embryo. German embryologist Hans Spemann and his student Hilde Mangold (1924) performed transplantation experiment on amphibians leading them to the concept of organizers. An organizer in embryology refers to the morphogenetic effect by which one organic tissue transmits a chemical substance that influences another embryonic part to produce a structure that otherwise could not come into existence. Their experiments showed that the dorsal lip of blastopore forms neural groove, notochord, mesoderm etc and is thus known as the Specman's primary organizer