Question

A cell has 12 pairs of sister chromatids in G2 of the cell cycle. How many pairs of homologous chromosomes should be seen at metaphase 2 of meiosis? Please choose the correct answer from the following choices, and then select the submit answer button. Answer choices 6 12 24 3 18

Answer 1

6 pairs of chromosomes

Step-by-step explanation:

The cell cycle consist of 4 phases:

G1 Phase

S Phase

G2 Phase

M Phase

G1 Phase

In the G Phase cell duplicates its organelles. In the example the cell has 6 pairs of chromosomes. In every pair of chromosomes one chromosome comes from the father and one chromosome comes from the mother. Although these chromosomes carry similar genetic information there are some differences between them.

S Phase

In the S Phase each chromosome is duplicated

In the example the cell has 12 pairs of chromosomes. Since each chromosome has a identical copy, they are called sister chromatids.

G2 Phase

In G2 phase cell prepares for mitosis. In the example the cell has 12 pairs of chromosomes.

M Phase

The M phase in the Meiosis is divided in Meiosis 1 and Meiosis 2

In Meiosis 1 pairs of sister chromatids align and undergo homologous recombination. For chromosome 1 , 2 pairs of sister chromatids align and mix their genetic content. In the example the cell has 12 pairs of chromosomes. At the end meiosis 1, 6 pairs of chromosomes goes to one side of the cell and the other 6 pairs of chromosomes go to opposite side of the cell. Finally the cell divides and two cells are formed, each cell has 6 chromosomes.

At the metaphase 2 Meiosis each pairs of homlogous chomosomes is aligned al the center of the cell. In the example you have 6 pairs of chromosomes in each cell aligned at the center.