A student uses a microscope to observe cells in the root tissue of an onion. He concludes that the cells are reproducing by mitosis.
Which hypothesis is supported by his conclusion?
a. The root tissue cells all have the same set of chromosomes.
b. The root tissue cells each have a unique genetic make-up.
c. The root tissue cells produce identical gametes..
d. The root tissue cells split to form stem cells.

The correct answer is option a. The root tissue cells all have the same set of chromosomes as it clearly explains the hypothesis.

Onions (Allium cepa L.) have eight relatively large chromosomal pairs (2n = 16) that can easily detect CA.

Mitosis creates two identical daughter cells, each containing the same number of chromosomes as the parent cell. In contrast, meiosis produces four unique daughter cells, each with half the number of chromosomes in the parent cell. Therefore, during the mitotic cell cycle, the DNA content per chromosome doubles in the S phase (each chromosome begins as a chromatid and becomes a pair of identical sisters in the S phase). However, the number of chromosomes remains the same.

Onion root cells have chromosome 16  in each cell after the G1, S, and  M phases.

Thus it concluded that mitosis causes root tissue cells to all to have the same set of chromosomes.

To know more about mitosis refer to the link :

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