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Anna007 [38]
3 years ago
9

Classify the following characteristics depending on if they describe events occurring in mitosis, meiosis I, or meiosis II.

Biology
1 answer:
Temka [501]3 years ago
5 0

Answer:

Mitosis events are:

Results in 2 genetically identical

diploid nuclei

A diploid number of sister

chromatids align at the spindle

equator during metaphase

Meiosis I events are:

Results in 2 genetically diverse

haploid nuclei

Homologous chromosomes align

at the spindle equator during

metaphase

Homologous chromosomes pair

up during prophase

Crossing-over occurs during

synapsis

Meiosis II events are:

Results in 4 genetically diverse

haploid nuclei

A haploid number of homologous

chromosomes align at the spindle

equator during metaphase

Explanation:

Mitosis is a type of cell division which produces two daughter cells that are genetically identical to the parent cell. In mitosis, the chromosome number of the parent cell is maintained in the daughter cells i.e. a diploid cell (2n) will undergo mitosis to produce two diploid (2n) daughter cells. During mitotic division, sister chromatids (replicated chromosomes) are involved in the division stages. i.e. diploid sister chromatids align at the equator of the cell during Metaphase and also sister chromatids are separated or pulled apart to opposite poles during Anaphase.

Meiosis, on the other hand, is a kind of cell division that results in daughter cells with a reduced number of chromosome (by half). Since the chromosome number is reduced, meiosis occurs in a two step division process viz: Meiosis I and II.

Meiosis I produces two genetically different daughter cells. The daughter cells have a reduced number of chromosomes i.e. from diploid (2n) to haploid (n). Meiosis I involves homologous chromosomes (similar but non-identical chromosomes received from each parent) which pair up to form a TETRAD structure in the Prophase stage. This structure allows for an exchange of chromosomal segment between non-sister chromatids of homologous chromosomes, a process called CROSSING-OVER. Crossing-over is what makes the daughter cells genetically different from the parent cell. Homologous chromosomes also aligns at the equator of the cell during Metaphase and later separates during Anaphase.

Meiosis II divides the two daughter cells produced in meiosis I into four genetically different daughter cells. Since the chromosome number has been reduced from diploid (2n) to haploid (n) in meiosis I when homologous chromosomes separate, haploid sister chromatids are involved in the stages of meiosis II i.e. haploid sister chromatids align at the equator of the cell during Metaphase and eventually becomes pulled apart during Anaphase.

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