Question

A student prepared a slide of onion peel and used a stain safranin solution. A. Why did he use the stain? B. Which parts of the cell are darkly stained? C. Name the round structure that appears roughly in the middle of cell.

Answer 1

A. He used the stain to make the colorless parts visible and to observe the entire structure more clearly.
C. Nucleus

Answer 2

Safranin is used as counter-strain. It is used in coloring onion cells because it gives color to the colorless cells which helps us to observe them. Iodine is also used to stain cytoplasm of yellow and white onion.

Onion epidermal cells will be darkly stained.

The structure that appears roughly in the middle of the cell is Nucleus.