Preparation of Metaphase Chromosome from Onion Cells

This presentation contains the principle, reagents and procedure for viewing chromosome and it's Metaphase state.Hope this ppt help for your reference.

1. PREPARATION OF METAPHASE CHROMOSOME FROM ONION CELLS By K. VISALI 2 ND M.Sc Biotechnology Annamalai University

2. MITOSIS Two identical cells- same number of chromosome Stages: P-prophase M- metaphase A- anaphase T- telophase

3. METAPHASE Second step Alignment of duplicated chromosome Karyotype – find chromosomal abnormalities Colchicine – arrest cell division at metaphase

4. Mitosis process visible in Somatic Cells Eukaryotic Cells Asexually reproducing Cells

5. Why onion used? MeristamatIc cells Monocot plant-large chromosome Mitosis varies Influenced

6. Reagent uses Sciff’s reagent- cytological study Fuchrin- dye to stain nuclear Potassium metabisulphite- slow’s down mitosis process HCl- breakdown the pectin Decolouring charcol- to remove coloured impurities

7. Protocol Onion on tile Grow root tips Take the newly grown roots

8. Cont …. Add glacial acetic acid : ethanol (1:3) 1 day incubation Place on slide Add 1 drop of 1N / 10 HCl

9. Cont…. 2-3 drop of acetocarmine stain Destain

10. Observation Different phases of mitosis observed.

11. THANK YOU