DNA structure & Replication

• DNA• Composition of DNA • Evidence for genetic material • Structure • Implications of the structure• DNA replication

DNA & Nucleotides

Evidence for genetic material: Griffith transformation

Evidence for genetic material

Avery, McCarty & Macleod

Hershey- Chase expt

Structure

Chargaff’s rules

Base Pairing Rules

Watson-Crick Model

• The double helix • base pairing rules • anti-parallel strands • bases/turn • major and minor

groove

Implications of the structure

• DNA replication

• Genetic Information stored in DNA molecule

DNA replication • DNA replication• Process of Replication

in E. coli• Origin of replication• Role of Primase: RNA

Primer • Elongation • Lagging strand

synthesis: Okazaki fragments

• Error rate of DNA synthesis

• Eukaryotic Replication

Meselson-Stahl Experiment: Semi-conservative replication

Origin of Replication

Initiation

Elongation

Replication Fork

Telomeres