Measures of Central Tendency: Mean, Median and Mode
DNA
1.
2. DNA – a polymer of deoxyribonucleotides.
The double helix shape is sometimes
called a twisted ladder.
It carries the genetic information.
A double stranded combination of sugars,
phosphates, and nitrogen bases.
3.
4. A nucleoside consists of a nitrogenous base covalently attached to a sugar but without the phosphate group.
A nucleotide consists of a nitrogenous base, a sugar and one to three phosphate groups.
5. STRUCTUR OF DNA
The secondary structure of DNA is
the double helix.
Two anti-parallel polynucleotide chains
wound around the same axis.
Sugar-phosphate chains wrap around
the periphery.
Bases (A, T, C, and G) occupy the
core, forming complementary A . T and
G . C Watson-Crick base pairs.
The DNA double helix is held together
mainly by- Hydrogen bonds.
7. Helical sense: right handed
Base pairs: almost perpendicular to
the helix axis; 3.4 Å
One turn of the helix: 36 Å;~10.4
base pairs
Minor groove: 12 Å across
Major groove: 22 Å across
In eukaryotic calls, DNA is folded
into chrometin.
Normally hydrated DNA: B-form DNA
8. DNA Tertiary structure
DNA double helical structure coils round
histones.
DNA bound to histones forms
nucleosomes(10nm Fibres).
Nucleosomes contain 146 nucleotides.
Nucleosomes
Any of the repeating globular subunit of
chromatin that consist of a complex of DNA
and histone.
Compaction of DNA in
eukaryotic chromosome
14. ACKNOWLEDGEMENT:
I Would Like To Acknowledge Our Department Faculties:
Mr. SHAILESH DIHORA
Miss. BANSRI
Miss. DRASHTI
For Providing Their Precious Guidance And Time