P20. MITOSIS

OBJECTIVES

The aim of this practice is to identify the phases of the mitosis in the root of an onion.

MATERIAL 

• Microscope

• Slide and coverslide

• Dropper

• Watch glass.

• Beaker

• Forceps

• Filter paper

• Scissors

• Bunsen burner

• Lighter.

• Needles. 

• Distilled water

• Orcein A

• Orcen B

• Onions

• Water

PROCEDURE

• We keep in a glass the bulb of an onion for a few days, the glass must contain water that is in contact with the roots until the roots measure 3mm.

• Then, we cut the roots and we put them in a watch glass and we add 2mL of Orcein A.

• Heat the watch glass with the orcein until we see gray vapors.

• Take the root and put it on the slide and add drops of orcein B. 

• We place the slide on filter paper, wrapping and tighting it.

• We cover it with the coverslide and we observe the results on the microscope.