The Following Question Refers to the Essential Steps in Meiosis

Multiple Choice

The following question refers to the essential steps in meiosis described below.
1. Formation of four new nuclei, each with half the chromosomes present in the parental nucleus
2. Alignment of tetrads at the metaphase plate
3. Separation of sister chromatids
4. Separation of the homologs; no uncoupling of the centromere
5. Synapsis; chromosomes moving to the middle of the cell in pairs
-When homologous chromosomes crossover, what occurs?

A) Two chromatids get tangled, resulting in one re-sequencing its DNA.
B) Two sister chromatids exchange identical pieces of DNA.
C) Specific proteins break the two strands and re-join them with their homologs.
D) Each of the four DNA strands of a tetrad is broken and the pieces are mixed.
E) Maternal alleles are "corrected" to be like paternal alleles and vice versa.