RP02 - Calculating mitotic index using plant cells

Question 1

Where in plants can cells undergoing mitosis be found?

Answer 1

Meristem tissues at the shoots and roots tips

Question 2

What is the mitotic index

Answer 2

The number of cells undergoing mitosis (visible chromosome) /Total cells in a sample

Question 3

Outline a procedure to prepare root tip slide

Answer 3

1. Warm 1M HCL to 60C in a water bath
2. Cut root tip using a scalpel and add to the HCL. Leave for five minutes
3. Remove from HCL and wash with distilled water
4. Cut the tip of the root tip sample and place on a slide
5. Add a few drops of a stain to make the chromosome visible

Question 4

State the hazards and precautions for reagents used in this procedure

Answer 4

• HCL is corrosive so avoid contact with skin and wear eye protection
• Toluidine Blue O stain is an irritant so avoid contact with skin and wear eye protection
• Scalpel cut away from fingers