In: Biology
Did Spemann’s results support or discredit Roux-Weismann hypothesis?
Roux-Weismann hypothesis of qualitative cell division, the theory posited that the unequal distribution of cellular material during each cell division caused physical differences in the developmental capacities of each cell. Spemann’s results effect now known as embryonic induction, an influence, exercised by various parts of the embryo, that directs the development of groups of cells into particular tissues and organs.
Spemann results disproved the Roux-Weismann hypothesis, as in the case of zygotes of salamander starts to divide, they get tied with a hair ligature, zygote is not completely seperated into half , nucleus is seen nin one side only, and the other side mainly contains the cytoplasm. The side which is nucleated get divide many times . At the stage of the zygote is composed of 16 cells, the nucleus go acroos to the anucleate side. After that the division takesplace in the cytoplasmic side. Thus both sides are developed normally and no nuclear material had been lost after many nuclear divisions.