Question

Which is incorrect about the process of gastrulation?
a. Movement and rearrangement of cells
b. Rapid division of cells by mitotic cell division
c. Formation of three germinal layers
d. Formation of archenteron

Answer 1

Hint: Gastrulation is the process which occurs during the embryonic development, after the formation of the blastula, it is nothing but the conversion of a bilaminar embryo to trilaminate. Where the third layer is formed in the embryo.

Complete answer:
- The formation of the embryo starts with the process of fertilization if the sperm and egg are fused together to form the zygote.
- Once this zygote forms, it undergoes cleavage and forms 2 cells, later 4 cells, and it reaches 16 cell stages called mortals, after that, it undergoes rapid cell division and forms a stage called a blastula.
- The inner cells of the blastula disintegrate and form the blastocoel, and this blastocoel is implanted to the endometrial uterine wall, and in this stage, it consists of only 2 layers, that is epiblast and hypoblast.
- A primitive streak forms and the anterior end of it’s called a primitive node.
- In this stage, the rearrangement of cells occurs, and the formation of germ layers occurs, this process is called gastrulation.
- The cells from the epiblast migrate and form invagination towards the primitive node and this invaginated cells displace the hypoblast and form the layer called the mesoderm, remaining epiblast cells convert to ectoderm and the hypoblast cells convert to endoderm
- And the primary which is formed during this gastrulation process is said to be the archenteron.

Hence, the correct answer is option (B).

Note: Gastrulation is a very crucial time during embryo formation, as in this stage the cells which are apart from one another, come close and all the rearrangement happens, as the future organs and all begin to start developing from this stage.