Question 1.

In order for an onion root to grow deep into the ground, the tip of the root undergoes rapid cell division with each cycle taking approximately 24 hours. The picture below shows a cross-section of a pressed onion root tip in which the DNA has been stained for visualization and is viewed under oil immersion. Because it is pressed, we no longer see the typical close relationship between cells.

a)        Choose a cell from interphase and each stage of mitosis (prophase, metaphase, anaphase, telophase).

b)      Using the method of your choice, indicate what a specific cell in this image looks like at each stage. You can draw the cell by hand or mark up the original image.

c)       If you do not think an example exists for a given stage, draw what it would look like.

d)       Justify your selections with a brief description of each stage to explain your choice.

(Hint: the most common appearance in the image above is interphase.)