2: More on mitotic index

Question 1

The actively dividing cells in the tip of the root is called a ______

Answer 1

Meristem

Question 2

In order to see chromosomes in cells, cells must be s______

Answer 2

separated

Question 3

You can separate cells by breaking down the m______ l______ of pectin

Answer 3

middle lamellae

Question 4

Name the chemical solution that will breakdown pectin

Answer 4

Hydrochloric acid (HCl)

Question 5

Name the stain used to see the chromosomes.

Answer 5

Aceteic orcein

Question 6

What concentration of HCl will be needed and at what temperature?

Answer 6

1 mol dm-3

60 dC

Question 7

Once the roots are submerged, leave them in for ____ minutes

Answer 7

5 minutes

Question 8

Take out roots and rinse with water.

What length should roots be cut to?

Answer 8

5 - 10 mm

Question 9

Place the root tips in ______ ________ for ___ minutes at ___ dC.

Answer 9

Aceteic orcein

5 minutes

60 dC

Question 10

Take roots out and with a drop of water tease root tip apart. This process is called ________

Answer 10

Maceration

Question 11

Place cover slip and gently squish tissue in order to put under the __________

Answer 11

microscope

Question 12

Mitotic index =

Answer 12

total no of cells in scope

Question 13

How could you estimate the time cells spend in each stage of mitosis?

Answer 13

               total no of mitotic cells

Question 14

Why is it difficult to identify stages in mitosis under a microscope?

Answer 14

Mitosis is a dynamic process,

many cells would be fixed during transition from one stage to another