Question

mitosis application question
a scientist is studying onion root tip cells under a microscope to investigate how fast they divide. she notices that some cells have clearly visible chromosomes lined up in the middle of the cell, while others show the chromosomes separating toward opposite poles.
questions:

1. identify which stages of mitosis these two observations represent.
2. explain why onion root tips are a good place to study mitosis.
3. predict what would happen if a cells spindle fibers were disrupted during mitosis.

Explanation:

1. When chromosomes are lined up in the middle of the cell, it is the metaphase stage of mitosis as the chromosomes align at the equatorial plate. When chromosomes are separating toward opposite poles, it is the anaphase stage as sister - chromatids are pulled apart by spindle fibers.
2. Onion root tips are a good place to study mitosis because they have a high rate of cell division. The meristematic tissue in the root tips is constantly growing and producing new cells, providing a large number of cells in various stages of mitosis for observation.
3. If a cell's spindle fibers were disrupted during mitosis, the chromosomes would not be properly separated. This could lead to an unequal distribution of chromosomes into daughter cells, resulting in cells with abnormal chromosome numbers (aneuploidy). This can cause genetic disorders or cell death.

Answer:

1. The first observation represents metaphase and the second represents anaphase.
2. They have a high rate of cell division due to meristematic tissue.
3. There would be an unequal distribution of chromosomes into daughter cells, potentially causing aneuploidy, genetic disorders or cell death.