Final answer:
To prepare microscope slides showing plant cells undergoing mitosis, samples should be taken from the tips of the roots, where meristematic tissue and active cell division occur.
Step-by-step explanation:
Abigail, a laboratory assistant, is tasked with preparing microscope slides of plants undergoing mitosis. The best place to obtain samples for viewing the cells in mitosis would be from the tips of the root of plants. This area of the plant contains meristematic tissue, specifically the apical meristem, which is known for its high rate of cell division.
Meristematic tissue is also found at the apex of the stem, but for ease of preparation and observation, the tips of the root are often preferred. In these regions, cells are actively dividing, allowing one to observe the different stages of mitosis more readily than in other parts of the plant, such as the leaves, flower petals, or the woody parts of a tree where cell division occurs less frequently or is more difficult to isolate and prepare for viewing.
When observing slides of root tips under a microscope, one can expect to see stages of mitosis such as prophase, metaphase, anaphase, and telophase within the cells located in this rapidly growing region.