Without _____,Humans Might Have a Tail

Question

Without _____,humans might have a tail.  
A) differentiation
B) epigenetics
C) cell migrations
D) apoptosis
E) the maternal gene effect

Accepted Answer

Apoptosis refers to programmed cell death during development. In humans, the cells that would have become a tail undergo apoptosis, leading to the absence of a tail in humans. Without apoptosis, humans might have retained a tail, as seen in other primates. Choice A (differentiation) refers to the process where cells become specialized in terms of structure and function. Choice B (epigenetics) refers to changes in gene expression that are inherited through cell division but not changes in the underlying DNA sequence. Choice C (cell migrations) refers to the movements of cells during development, which are important for the formation of tissues and organs. Choice E (the maternal gene effect) refers to the influence of maternal genes on the development of the embryo. While it may contribute to the absence of a tail in humans, it is not the primary factor responsible.