EMBRYOLOGY
NERVOUS SYSTEM
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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neurulation
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gastrulation
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somite migration
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development of spina bifida
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Detailed explanation-1: -The beginning of gastrulation is marked by the appearance of a groove in the caudal end of the epiblast layer known as the primitive streak .[6] Thus, the formation of primitive steak firmly establishes the cranial/caudal axis. The primitive streak initially forms via a thickening of cells near the connecting stalk.
Detailed explanation-2: -Gastrulation. Late in the second week after fertilization, gastrulation occurs when a blastula, made up of one layer, folds inward and enlarges to create a gastrula. A gastrula has 3 germ layers–the ectoderm, the mesoderm, and the endoderm.
Detailed explanation-3: -After fertilization, the zygote undergoes cleavage to form the blastula. The blastula, which in some species is a hollow ball of cells, undergoes a process called gastrulation, in which the three germ layers form.