Question

During meiosis, a defect occurs in a cell that results in the failure of microtubules, spindle fibers, to bind at the kinetochores, a protein structure on chromatids where the spindle fibers attach during cell division to pull sister chromatids apart. Which of the following is the most likely result of such a defect?

Answer 1

Answer: Aneuploidy

Step-by-step explanation:

Meiosis is the cell division by which daughter cells are obtained with half of the chromosome sets that the originall cell had but which have complete information for all the structural and functional features of the organism to which they belong. It produces gametes, which are sperm and eggs.

During metaphase, the chromosomes are already fully condensed and located in the centre of the cell, forming the equatorial plate. They are attached to the fibres of the chromatic spindle by the kinetochore of each chromosome. The chromatids of the chromosomes are separated by the centromere because the fibres of the spindle are shortened. Each chromatide is directed towards a centriolus, located one at each pole of the cell. The same number of chromatids go to each pole of the cell, as the chromosomes have been divided into two chromatids.

However, if there is failure of the spindle fibers to bind at the kinetochores, they can not pull the sister chromatids apart. The new cells will not receive the correct number of chromosomes in the gametes, which is known as aneuploidy.

Answer 2

Explanation:PRC1 accumulates on the central spindle in anaphase,

and suppression of PRC1 expression causes failure of microtubule interdigitation.