Simulated Microscope Activity: View of an Onion Root Tip
The actively dividing root cells are located near the tip of a root. A dye is applied to a sample of these cells. The chromosomes, of the cells, accept the dye and appear bright red compared to other cell structures.
For the following questions, identify the correct cells by referencing their location on the chart. Name the ROW letter first, followed by the COLUMN number. For example, the last cell in the second row is correctly labelled as B-12.
The majority of cells do not have stained chromosomes. Most of these cells are in interphase.
The DNA is uncoiled as chromatin and cannot be detected by a light microscope.
For the following list two cell examples.
(a) Two cells that illustrate the mitotic phase prophase.
(b) Two cells that represent cytokinesis.
(c) Metaphase is illustrated by two cells labelled:
(d) Two root cells that illustrate anaphase.
(e) Telophase can be represented by cells:
(f) Two daughter cells are evident at position
Technically speaking, only when DNA condenses in prophase can the stained chromosomes be visible with a light microscope.
Because the phases are a continuous sequence, late anaphase will look like early telophase.
Interphase is characteristically a diagram of a normal cell. The nucleus is visible with a nucleolus inside. The chromatin, although stained, is invisible during interphase.
In plant cells, a cell wall is formed from the middle towards the outer cell walls.