Core Practicle (X) Root Tip Squash

Question 1

What is the aim

Answer 1

To observe cells undergoing mitosis

Question 2

Why is warm HCL (1 mol) used

Answer 2

To break down the middle lamela between each cell, separating the cells

Question 3

What are the control variables in the mitosis practical

Answer 3

Amount of HCL - using too little will not break down the middle lamela

Amount of Toluene blue - using large amounts of toluidine blue will make it hard to identify the chromosomes

Question 4

What does Toluidine Blue stain

Answer 4

Chromosomes of a cell

Question 5

What are the risks in the mitosis experiment

Answer 5

Hcl - is a skin iritant
Toluidine blue - harmfull when injested + stains clothes

Glass slides - braking fragile glass slides releases shards of glass

Question 6

What is the method of the mitosis practical

Answer 6

-Cut the garlic root tips to 3.5mm with scissors (white section of the roots

-Place the cut tip into warm HCl for 5 mins

-Wash off the HCl with cold water for 5 mins, then dry with blotting paper

• Using forceps place the root tip on a glass slide and macerate (mounted needle)
• Add a small drop of toluidine blue (allow it to be absorbed for 2mins)
  -remove excess stain + place a cover slip on
• observe the cells at ×400 magnification
  -record the phases the cells are in and state the mitotic index