The zygote is at first surrounded by a fertilization membrane. What is the purpo
ID: 164579 • Letter: T
Question
The zygote is at first surrounded by a fertilization membrane. What is the purpose of this membrane? Why doesn't the starfish embryo have a neural tube? In the starfish, all of the embryo cells contribute to the formation of the starfish. Yet in the human, a majority of the early embryo cells do not contribute to the formation of the person but are used for other purposes. Name three things these nonperson-forming cells form and tell why is it necessary to use these embryonic cells in this manner.Explanation / Answer
1. The hard membrane surrounded the zygote is called as fertilisation layer, which is nothing but transformed vitelline membrane of ovum, as it is outer structure of plasma membrane uses for signalling process, after fertilisation this acts as barrier to block another spem to enter after fertilisation.(Polyspermy)
2.Under evolution the embryo of echinoderms dont have neural tube, after formation of Brachiolaria larvae, the orrfice developed into neural tube around the mouth, it doesnt have brain and neural network.
Related Questions
Navigate
Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.