Structure and Functions of DNA.

Structure and functions of DNA.
Human Anatomy and Physiology- 2
Soniya.M.Sunil
3rd year B.Pharm
Mar Dioscorus College of Pharmacy.

1. DNA
•DEOXYRIBO NUCLEIC ACID

2. INTRODUCTION
uNucleicacidsaretheorganicmaterialspresentinall
organismsintheformofDNAandRNA.
uTheDNAstructuredefinesthebasicgeneticmakeupofour
bodyaswellasnearlyalllifeonearth.

3. WHAT IS DNA?
uDNA is a group of molecules that is responsible for carrying and
transmitting the hereditary materials from parents to offspring.
uDNA is known as Deoxyribo Nucleic Acid. It has a unique molecular
structure. It is present on both prokaryotic and eukaryotic cells.
uDNA was first recognised by swiss biologist Johannes Friedrich
Miescherin 1869.

4. STRUCTURE OF DNA
•The structure of DNA is described as double
helix.
•It is a nucleic acid, which is made up of
nucleotides and each nucleotide composed of
sugar, phosphate group and nitreogenous
bases.
•The structure was discovered byJames Watson
and Francis Crick.
•The nitreogenous bases are adenine, thymine,
guanine and cytosine.

5. uThese four nitrogen bases pair together in the following way: adeninewith
thymineand cytosinewith guanine.
uAdinine and guanine form a pair of purines and thymine and cytosine form a
pair of pyrimidines.
uThe two strands run in opposite direction and the strands are helically twisted.
uThe pitch of the helix is 3.4nm and the distance between the two
consecutive base pair is 0.34nm.
uDNA coils up forming chromosomes and there are 23 pair of chromosomes
in our body.
.

6. FUNCTIONS OF DNA
uReplication process -Transmitting the hereditary materials from
parents to offspring.
uHave a crucial role in production of proteins.
uTakes part in cell division.
uGene therapy.