• Skip to primary navigation
  • Skip to main content
  • Skip to primary sidebar

Snab Biology

  • Core Practicals
  • About
  • Contact

Observing Mitosis

Published: Feb 7, 2017 Modified: Nov 27, 2019 / By Dr. Isa About 3 minutes to read this article. . . Find our Privacy Policy here . . Leave a Comment

Core Practical 5 – From Topic 3 (Voice of the Genome)

Contents hide
1 Core Practical 5 – From Topic 3 (Voice of the Genome)
1.1 Aim
1.2 Equipment
1.3 Method
1.4 Results & Calculations
1.5 Conclusion
1.6 Evaluation Points

view of mitosis

Aim

To be able to prepare and stain a root tip to observe the stages of mitosis under a microscope.

Equipment

  • Garlic roots
  • Sharp knife
  • 1moldm¯³ of  hydrochloric acid
  • Acetic alcohol
  • Orcein ethanoic stain
  • Ice-cold distilled water
  • Water bath (60 ̊C)
  • 2 watch glasses
  • Test tube
  • Test tube rack
  • 2 pipettes
  • Microscope slides
  • Forceps
  • Mounted needle
  • Filter paper
  • Microscope with x100 & x400 magnification

 

Method

  1. Place a test tube of 2cm³ HCl (1moldm¯³) into a test tube rack in a 60 ̊C water bath.
  2. Cut off 1-2cm of a root tip from garlic root. Put the tip in a watch glass containing 2cm³ of acetic alcohol for at least 12 minutes.
  3. Remove the tip and then place into another watch glass containing 5cm³ of ice cold distilled water. Leave for 4-5 mins, and then remove and dry.
  4. Place the tip into the heated HCl for 5 minutes then repeat the process again by placing tips back into acetic alcohol etc. Tip: The tips will be very fragile at this point.
  5. Transfer 1 tip onto a microscope slide and cut 4-5mm from the growing tip (site of mitosis) and keep it.
  6. Gently break up (macerate) the root tip with a mounted needle.
  7. Add 1 small drop of orcein ethanoic stain and leave for 2 minutes.
  8. Add a coverslip and blot with filter paper.
  9. View under a microscope and identify the stages of mitosis.

 

Results & Calculations

The percentage of cells in each stage of mitosis can be observed and noted down. A Mitotic index can also be formed:

Number of cells containing visible chromosomes ÷ Total number of cells in the field of view

Conclusion

 Mitosis consists of four different sections: prophase, metaphase, anaphase and telophase.

Prophase – Chromosomes condense (chromatids joined by centromere)
– Spindle fibres join to both centrioles
– Nuclear envelope breaks down

Metaphase – Centromeres attach to spindle fibres at the equator.
– Chromosomes line up

Anaphase – Centromeres split
– One chromatid from each chromosome is pulled to either end of the cell

Telophase – Chromosomes unravel
– Two nuclear envelopes reform

Cytoplasmic division then occurs where the cell surface membrane divides to form two daughter cells. Interphase then takes place (G1, S and G2 sub-phases). The cell cycle then repeats.

Evaluation Points

  • Low resolution of microscope (systematic error) – use a more detailed microscope with a greater magnification
  • Human error in counting numbers of cells (random error) – take a picture of the image in the lens as this should make counting easier
  • Not enough time in the solutions to enable successful maceration or staining (systematic error) – leave for 5 minutes longer in future trials
Previous Post: « The Effect Of Changing Enzyme Concentration On The Rate of Reaction
Next Post: Looking At Plant Stems »

Reader Interactions

Leave a Reply Cancel reply

Your email address will not be published. Required fields are marked *

This site uses Akismet to reduce spam. Learn how your comment data is processed.

Primary Sidebar

Articles

Students studying

Resource Recommendations

Garlic And Mint As Antibiotics

The Strength Of Plant Fibres

Investigating Plant Mineral Deficiencies

Looking At Plant Stems

view of mitosis

Observing Mitosis

experiment equipment on table

The Effect Of Changing Enzyme Concentration On The Rate of Reaction

The Effect of Temperature on Cell Membranes

Glass with orange huice

Measuring the Content of Vitamin C in Fruit Juice

Effect of Caffeine on Daphnia Heart Rate

Recent Comments

  • ryan on Effect of Caffeine on Daphnia Heart Rate
  • tutorial on Using A Spirometer To Measure Tidal Volume And Breathing Rate
  • anon on The Effect Of Different Antibiotics On Bacteria
  • Olivia Eastman on The Strength Of Plant Fibres
  • 777 Directory on The Strength Of Plant Fibres

Copyright © 2020 Snab Biology on the Foodie Pro Theme

We are using cookies to give you the best experience on our website.

You can find out more about which cookies we are using or switch them off in settings.

Snab Biology
Powered by  GDPR Cookie Compliance
Privacy Overview

This website uses cookies so that we can provide you with the best user experience possible. Cookie information is stored in your browser and performs functions such as recognising you when you return to our website and helping our team to understand which sections of the website you find most interesting and useful.

Strictly Necessary Cookies

Strictly Necessary Cookie should be enabled at all times so that we can save your preferences for cookie settings.

If you disable this cookie, we will not be able to save your preferences. This means that every time you visit this website you will need to enable or disable cookies again.