The darkly stained, rod shaped bodies visible under light microscope in a cell during metaphase stage of mitosis are called chromosome.

1. TOPIC: ARCHITECTURE OF
CHROMOSOME IN PROKARYOTES AND
EUKARYOTES
WELCOME TO CLASS
PRESENTATION OF
CYTOGENETICS
PRESNTED BY:- VIPIN PANDEY

2. S. NO PROKARYOTS S.NO EUKARYOTS
1 These are primitive organism like
bacteria, virus, & BGA.
1 These are higher organism other
than bacteria, viruses, & BGA .
2 They do not have well defined nucleus
and nuclear membrane.
2 They have well defined nucleus
surrounded by a nuclear membrane.
3 The DNA is free of structural proteins. 3 The DNA is tightly associated with
specific proteins.
4 Prokaryote cell has DNA plus
ribosomes.
4 Eukaryote cell has nucleus and
various cell organelles.
5 Nucleus is absent. 5 Nucleus is present.
WHAT DIFFERENCE IN
PROKARYOTES & EUKARYOTS CELLS

3. ∗ The darkly stained, rod shaped bodies
visible under light microscope in a cell
during metaphase stage of mitosis are
called chromosome.
CHROMOSOME
WHEAR IS FOUND CHROMOSOME?
∗ Chromosome is found of all cells .
WHAT IS CHROMOSOME ?
Discovered by :- Strasburger, 1875; Coined term by :- Waldeyer, 1888

4. CHROMOSOME
WHEAR IS FOUND CHROMOSOME IN CELLS ?
∗ Chromosome is found of all cells in
the nucleus.
Discovered by :- Strasburger, 1875; Coined term by :- Waldeyer, 1888

5. ∗ DNA is very long.
WHY GENES/DNA ARE PACKEDED ON FORM OF CHROMOSOME ?
CHROMOSOME
~13.6cm.
~22cm.
~5.44m.
WHEAT 3 TYPES
GENOMIC
DNA IS, PACKED IN
21 CHROMOSOMES
RICE GENOMIC DNA ARE
PACKED IN 12 CHROMOSOME
SORGHUM GENOMICDNA ARE
PACKED IN 10 CHROMOSOME

6. ∗ Naked DNA is unstable in nucleus or cytoplasm .
∗ Time of cell division chromosome easily distribute
parental to daughter cells by the centromere.
∗ Easily regulation of gene action.
WHY GENES/DNA ARE PACKEDED ON FORM OF CHROMOSOME ?
CHROMOSOME

7. ∗Precise distribution of DNA parental to daughter cells. In Somatic cell 2n to 2n;
CHROMOSOME

8. ∗Precise distribution of DNA parental to daughter cells. In
Gametic cell 2n to n.
CHROMOSOME
2n
n
n
n
n

9. ∗ Prokaryotic chromosome is consists of single circular,
double-stranded DNA molecule.
∗ It has no histone protein.
∗ Chromosomes are stored in nucleoid in which DNA in
binding to some proteins.
∗ The genome of prokaryotes is often significantly
larger than the cell it self. How it is possible?
∗ Contain only one copy of the gene (hapolid).
Prokaryotic chromosome

10. ∗ Non essential genes are stored
outside of chromosome in plasmid.
∗ It is circular molecule of DNA
but the total length of DNA
molecule is very large 1100µ.
Nucleoids of prokaryotes'
AGCTAGCTAGCTAGCTAGCTAGCTAGCTAG
TCGATCGATCGATCGATCGATCGATCGATC
1100µ

11. ∗Diameter of fully expanded E.coli circular
DNA is 350µ, while an E.coli cell has the
diameter of only 2-5µ.
∗In chromosome have 40-50 loops or domains
found, which are connected or binding with RNA
or proteins.
∗Loops are coiled and, coiled loops are
called super coiled loops; it is attached
with central scaffold protein
Nucleoids of prokaryotes'
5µ

12. ∗ In the bacteria other than a big chromosome 1-20 covalently closed
circular DNA molecules structure which includes genetic
information & presenting in cytoplasm are called plasmids.
∗ It have stored non essential genes.
∗ It have capable of replication.
Plasmid

13. ∗ Under light microscope each
chromosome consists of several parts
like-
∗ Centromere / primary constriction.
∗ Chromatids.
∗ Secondary constriction & satellite.
∗ Telomere.
∗ Chromomere.
∗ Chromonema.
∗ Matrix.
Eukaryotic chromosome

14. ∗ Centromere / primary constriction.
∗ Chromatids.
Eukaryotic chromosome

15. ∗ Chromomere.
∗ Chromonema.
Eukaryotic chromosome

16. Chromosome packaging
Nucleosome solenoid model

17. ∗ Artificial chromosome refers to synthetic
chromosome consisting of fragments of DNA
integrated into a host chromosome.
∗ It is two type-
∗ YAC-Yeast Artificial chromosome
∗ BAC-Bacterial Artificial Chromosome
Artificial chromosome

18. YAC-Yeast Artificial chromosome
∗Yeast artificial chromosome.
∗Self-replicating elements.
∗Can insert segments up to 1000-
2000 kb pairs.
∗Can replicate any inserted DNA via
transfer to yeast cells.

19. ∗ Tel – telomeres.
∗ Cen – centromere.
∗ Ori - Origin of replication.
∗ Selectable markers.
∗ Restriction enzyme recognition sites.
Essential elements for YACs

20. YAC-Yeast Artificial chromosome

21. ∗ BAC is cloning vector system in E.coli
developed by Mel Simon and his colleagues.
∗ It is developed to alternative of YAC vectors.
∗ BAC is maintained in E.coli as large single
copy plasmids that contain inserts of 150-
350kbp.
BAC-Bacterial Artificial Chromosome

22. BAC-Bacterial Artificial Chromosome

23. ∗ It is used to map genes in genomes.
∗ It is also useful in testing f function of genes.
∗ It is used to make transgenic plants.
∗ It is used for study of proteins structure.
∗ It is used to desired gene cloning.
Uses of artificial chromosome

24. ∗ Chromosomes, which differ significantly from normal
chromosomes.
∗ It is differ from normal chromosome to either morphology or
function.
∗ It is three types:-
1.Lampbrush chromosome
2.Polytene chromosome or giant chromosome
3.B chromosome
Special types of chromosome

25. ∗ Lampbrush chromosome are have large number of loops.
∗ Loops giving a lampbrush appearance.
∗ They are found in oocyte nuclei of both vertebrates &
invertebrates.
1.Lampbrush chromosome

26. ∗ The multiple replicates of the same chromosome holding together
in a parallel fashion resulting in very thick chromosome are known
polytene chromosome.
∗ Found in certain tissues e.g., salivary glands of larvae, gut
epithelium, Malphigian tubules and some fat bodies, of some
Diptera (Drosophila, Sciara, Rhyncosciara)
∗ Giant chromosomes are made up of several dark staining regions
called “bands”.
∗ It can be separated by relatively light or non-staining “interband”
regions
2.Polytene chromosome or giant chromosome

28. Thank you