CH1

I. Genes are DNA

II. Chemical Characteristics of DNA

III. DNA Size and Capacity

IV. Basic Genetics Review

1.1 Introduction

The Genome includes all DNA found in a cell and is functionally divided into genes

1.2 Historical Perspective

DNA is the genetic material

genetic properties can be transferred from one bacterial strain to another by extracting DNA from the first strain and adding it to the second strain

Phage infection showed that DNA is the genetic material of viruses

DNA and protein components of bacteriophages can be labeled with different radioactive isotopes

only the DNA is transmitted to the progeny phages produced by infecting bacteria

bacterial transformation was the first thing to support that DNA is genetic material of bacteria

Genes can be made of RNA (Viruses)

Bacteriophage

virus particle by itself

some viruses contain DNA genes, but some viruses have RNA genes, either double- or single-stranded

no metabolic activity of its own

if virus infects a host cell, the cell begins to make viral proteins

viral genes are replicated and newly made genes with viral protein assemble into virus particles

in the laboratory, phage DNA can be used to introduce new genetic traits into animal cells or whole animals

1.3 DNA is Made of Polynucleotide Chains, Nitrogenous Bases and Sugar-Phosphate Backbone

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RNA has uracil instead of thymine

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One end of the chain (conventionally written on the left) has a free 5' end and the other end of the chain has a free 3