CP3 Squash root Flashcards
1
Q
Where in plants can cell undergoing mitosis be found?
A
- Meristem tissue and roots + shoot.
2
Q
What is the mitotic index?
A
- Ratio of number of cells undergoing mitosis to total number of cells in a sample.
3
Q
Outline the procedure to prepare a root tip slide.
A
- Heat 1M HCl to 60°C.
- Cut root tip w/ scalpel + add to HCl for 5 mins.
- Remove from HCl + wash w cold distilled water.
- Dry + place on slide.
- Macerate w/ needle to spread cells.
- Add few drops of stain.
4
Q
Why is stain added?
A
- To make c’somes visible.
5
Q
What is the formula for mitotic index?
A
- Mitotic index = number of cells w/ visible c’somes / total number of cells.
6
Q
What are the hazards and precautions for reagents used in this experiment?
A
- HCl - Corrosive - avoid contact w/ skin + wear eye protection.
- Stain - irritant - avoid contact w/ skin + wear eye protection.
- Scalpel - cut away from fingers.
7
Q
Why is root tip placed in hot HCl?
A
- Dissolves middle lamella to break up cellulose wall.
- Allows stain to permeate + be squashed more easily.
8
Q
Why is sample squashed?
A
- To flatten + reduce number of layers.
- Reducing overlap - cell can be seen more easily.
