Lecture #7 - Dna Replication

Ogan Gurel, MD Biology 301 Lecture # 7 Roosevelt University

Biology 301 Cellular and Molecular Biology Spring 2002

Lecture # 7: DNA Replication

Ogan Gurel, MD Biology 301 Lecture # 7 Roosevelt University

Overall outline  DNA as the genetic material  DNA Replication  DNA Repair  DNA > RNA > Protein (revisited)

Ogan Gurel, MD Biology 301 Lecture # 7 Roosevelt University

DNA as the genetic material  Transformation of bacteria  Phage DNA entering a cell  Hershey - Chase experiment  The structure of a DNA strand  Purines & Pyrimidines  X-ray diffraction pattern of DNA  The Double Helix  Base pairing in DNA  DNA Replication

Transformation of bacteria

Ogan Gurel, MD Biology 301 Lecture #7 Roosevelt University

Phage DNA entering a cell

Ogan Gurel, MD Biology 301 Lecture #7 Roosevelt University

Hershey - Chase experiment

Ogan Gurel, MD Biology 301 Lecture #7 Roosevelt University

The structure of a DNA strand

Ogan Gurel, MD Biology 301 Lecture #7 Roosevelt University

Purines & Pyrimidines

Ogan Gurel, MD Biology 301 Lecture #7 Roosevelt University

X-ray diffraction pattern of DNA

Ogan Gurel, MD Biology 301 Lecture #7 Roosevelt University

The Double Helix

Ogan Gurel, MD Biology 301 Lecture #7 Roosevelt University

Base pairing in DNA

Ogan Gurel, MD Biology 301 Lecture #7 Roosevelt University

Ogan Gurel, MD Biology 301 Lecture # 7 Roosevelt University

DNA Replication  A model for DNA replication: the basic concept  Three models of DNA replication  The Meselson-Stahl experiment tested three hypotheses of DNA replication  Replication begins at the “origin”  Incorporation of a nucleotide into a DNA strand  The two strands of DNA are anti-parallel  Synthesis of leading & lagging strands  Priming DNA synthesis  The main proteins of DNA replication and their functions  A summary of DNA replication

A model for DNA replication: the basic concept

Ogan Gurel, MD Biology 301 Lecture #7 Roosevelt University

Three models of DNA replication

Ogan Gurel, MD Biology 301 Lecture #7 Roosevelt University

The Meselson-Stahl experiment tested three hypotheses of DNA replication

Ogan Gurel, MD Biology 301 Lecture #7 Roosevelt University

Replication begins at the “origin”

Ogan Gurel, MD Biology 301 Lecture #7 Roosevelt University

Incorporation of a nucleotide into a DNA strand

Ogan Gurel, MD Biology 301 Lecture #7 Roosevelt University

The two strands of DNA are anti-parallel

Ogan Gurel, MD Biology 301 Lecture #7 Roosevelt University

Synthesis of leading & lagging strands

Ogan Gurel, MD Biology 301 Lecture #7 Roosevelt University

Priming DNA synthesis

Ogan Gurel, MD Biology 301 Lecture #7 Roosevelt University

The main proteins of DNA replication and their functions

Ogan Gurel, MD Biology 301 Lecture #7 Roosevelt University

A summary of DNA replication

Ogan Gurel, MD Biology 301 Lecture #7 Roosevelt University

Ogan Gurel, MD Biology 301 Lecture # 7 Roosevelt University

DNA Repair  Excision repair of DNA damage  The end-replication problem  Telomeres and telomerase

Excision repair of DNA damage

Ogan Gurel, MD Biology 301 Lecture #7 Roosevelt University

The end-replication problem

Ogan Gurel, MD Biology 301 Lecture #7 Roosevelt University

Telomeres and telomerase

Ogan Gurel, MD Biology 301 Lecture #7 Roosevelt University

Ogan Gurel, MD Biology 301 Lecture # 7 Roosevelt University

DNA > RNA > Protein (revisited)