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

Question

Quizplus · Accepted Answer

The grey crescent in amphibian eggs contains cytoplasmic determinants that are critical for normal development. If the first cleavage plane fails to divide the grey crescent, only the daughter cell with the grey crescent will have access to these determinants and develop normally. The other daughter cell will lack these determinants and likely undergo apoptosis or develop abnormally. This occurs because amphibians are not totipotent at this stage, but rather rely on differential gene expression and cytoplasmic determinants to specify cell fate.

If an Amphibian Zygote Is Manipulated So That the First