13-2TYU - Campbell Biology

Question

The two homologs of a pair move toward opposite poles of dividing cells during 

1. mitosis
2. meiosis I
3. meiosis II
4. fertilization

Step-by-Step Solution

Answer

1. The option“mitosis” is false.
2. The option “meiosis I” is true.
3. The option“meiosis II” is false.
4. The option “fertilization” is false.

Step 1: Description of cell division

Cell division is the process of splitting up parent cells into two daughter cells. It maintains the cell population, growth, and repair. The cell division process is regulated by cell cycle regulation.

Step 2: Explanation of option (A)

Mitosis is the process that creates identical daughter cells. This process replaces the damaged cells and repairs cell parts. Spindle fibers attach to kinetochores and separate the sister chromatids.

Instead, the chromosomes are divided into sister chromatids.

Therefore, the given option is false.

Step 3: Explanation of option (B)

Meiosis I is a different process that occurs in sex cells. This process produces haploid cells from the diploid cells.

                       

Meiosis I is the process in which the separation of chromosomes takes place into two homologs. It contains one paternal and maternal chromosome.

Therefore, the given option is true.

Step 4: Explanation of option (C)

Meiosis II is the process in which the sister chromatids separate into haploid daughter cells. This process is similar to mitosis. The separation of homologs takes place before the starting of the meiosis II phase. 

 

The chromosomes segregated in meiosis I, in turn, undergo further separation in meiosis II.

Therefore, the given option is false.

Step 5: Explanation of option (D)

Fertilization is the fusion of male and female gamete after coitus. This process results in the formation of offspring.

 

The fusion of male and female gamete results in the union of homologous chromosomes that are separated and placed in the gametes before fertilization. 

Therefore, the given option is false.