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Jaina Biology
Cleavage and Gastrulation in the Human Egg
After fertilization Kalala 13 (zygote or flat disc) is formed within seven days, next arbuda 14 (slightly hard mass or solid ball of cells or cylindrical embryo) develops within seven days; pesis15 (tissues) are formed out of arbuda (solid ball of cells); ghana 16 with four angles is next formed from peśís, i. e. blastula and so on.
That is to say, "the early cleavage of the human or mainmalian egg resembles that of Amphioxus in forming cluster of cells called blastocyst. After this the mainmalian egg differs in that the mass of cells divides into two parts-an outer, hollow sphere of cells and attached to one side of this, an inner, solid ball of cells (i.e. arbuda). The outer sphere is one of the foetal membranes, the other embryonic membranes develop from the inner, solid ball of cells. The inner ball proceeds to form a gastrula, consisting of ectoderm and entoderm. Within the inner cell mass two cavities form simultaneously. The upper one is the cavity of the amnion, lined with ectoderm. The lower one is the cavity of both the yolk and the primitive gut, lined with entoderm. Between the two cavities the cells spread out in the shape of a flat, two-layered plate, from which the embryo develops. At what is to become the posterior end of the embryo this plate connects with the outer chorion by a group of cells known as the body stalk. Into the body stalk grows the (non-functional) allantois which has developed as a tube from the rear end of the entodermal (yolk) sac. Thus we find, after about two weeks of development that the human embryo consists of a flat, two-layered disc, about 0.01 inch across, and a stalk which connects the disc with the outer chorion.'17
"In all animals (except sponges and coelenterates) a third layer of cells, the mesoderm develops between ectoderm and entoderm.”'18
Notochord (Prestage of Pitthakaramdaga backbone )
The reference to the vertibral column (Pitthakaramdaga ) in Jaina Biology presupposes the notochord (prestage of Pitthakaramdaga) which is a flexible unsegmented, skeleta120 (karamda ) which extends longi13. Tandula Veyaliya 2 p. 6. 14. lbid 15. lbid 16. Ibid 17. Biology, p. 435 18. Ibid 19. Taodula Veyaliya, 16, p. 35
The short lived 'Noto Chord' is replaced by bickbone in developed child. 20. Ibid
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