Question

What is the arrangement of homologous chromosomes in mitosis, and why is this important?

A. A cell's homologous chromosomes line up independently (individually) along the plane of division; this allows for the daughter cells to have the same chromosome number as the parent cell
B. A cell's homologous chromosomes line up independently (individually) along the plane of division; this sets up for the first division to cut the chromosome number of the daughter cells in half
C. A cell's homologous chromosomes associate next to each other and cross over: this allows for the daughter cells to have the same chromosome number as the parent cell
D. A cell's homologous chromosomes associate next to each other and cross over: this sets up for the first division to cut the chromosome number of the daughter cells in half

Answer 1

In mitosis, homologous chromosomes line up independently along the plane of division which ensures that each daughter cell maintains the same number of chromosomes as the parent cell, unlike in meiosis where chromosome number is halved.

Step-by-step explanation:

The arrangement of homologous chromosomes during mitosis is such that each chromosome is lined up independently along the plane of division during metaphase of mitosis. This aligning occurs with the individual chromosomes' kinetochores facing opposite poles. Importantly, the homologous chromosomes do not pair up as they do during meiosis; there is no crossing over in mitosis. The significance of this arrangement is that during anaphase, the sister chromatids are separated and each daughter cell receives one copy of each chromosome, maintaining the same chromosome number as the parent cell. This is in contrast to meiosis, where homologous chromosomes do pair up and crossover, and the chromosome number is halved in the daughter cells as a part of sexual reproduction to form gametes.