Reuqired pratical 2

Question 1

Calculating Mitotic Index using Plant Cells

Question 2

Where in plants can cells undergo mitosis be found?

Answer 2

Meristem tissue

Question 3

What is the mitotic index?

Answer 3

The ratio of cells undergoing mitosis to the total number of cells in a sample.

Question 4

Outline the procedure to prepare a root tip slide/

Answer 4

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

Question 5

State the formula for the mitotic index

Answer 5

Mitotic index = number of cells with visible chromosomes / Number of cells in sample

Question 6

State the hazards and precautions for reagents used in this procedure

Answer 6

HCL - corrosive, avoid contact with skin, wear protection

Toluidine Blue O stain - irritant, avoid contact with skin, wear eye protection

Scalpel - cut away from fingers