Nucleic AcidDr. Aarab Khan Lund

Nucleic Acids• Nucleic acids are molecules that store information for cellular

growth and reproduction• There are two types of nucleic acids:

- deoxyribonucleic acid (DNA)-ribonucleic acid (RNA)

• A nucleotide consists of a nitrogenous base, a pentose sugar and a phosphate group:

Nitrogen Bases

Pentose Sugars• There are two related pentose sugars:

- RNA contains ribose- DNA contains deoxyribose

• The sugars have their carbon atoms numbered with primes to distinguish them from the nitrogen bases

Nucleosides and Nucleotides• Nitrogen base+Pentose Sugar =Nucleoside• Nitrogen base+Pentose Sugar+Phosphate group= Nucleotide

Types of Nucleotides

• Mononucleotide• Dinucleotide• Polynucleotide

DNA (Hereditary material)• Griffith• None virulent bacteria->Virulent bacteria.• Hershy and Chase• Bacteriophage-DNA-Host-more phages.• All nucleotides of DNA, phosphate and

deoxyribose sugars are always common but nitrogenous bases are different.

• Each DNA has specific sequences of nitrogenous bases. It encodes vaste amount of information

Gene Expression• Transcription and Translation.

Continue• Initiation of protein synthesis occurs when a mRNA attaches to

a ribosome.