If an amphibian zygote is manipulated so that the first cleavage plane fails to divide the grey crescent, then
A)the daughter cell with the entire grey crescent will die.
B)both daughter cells will develop normally because amphibians are totipotent at this stage.
C)only the daughter cell with the grey crescent will develop normally.
D)both daughter cells will develop abnormally.
E)both daughter cells will die immediately.

Question

Quizplus · Accepted Answer

The grey crescent is an important structure during early amphibian development because it contains the maternal determinants that specify the formation of the dorsal axis. If the first cleavage plane fails to divide the grey crescent, then only one daughter cell will contain these maternal determinants and will develop normally, while the other daughter cell will lack these determinants and will likely die or develop abnormally. Therefore, option C is the correct choice.

If an Amphibian Zygote Is Manipulated So That the First