I. History of DNA

A. Friedrich Miescher

1. Identified DNA in the nucleus of white blood cells in 1871

2. It was a sugary, phosphate-rich chemical which he called

nuclein

C. Oswald Avery- DNA is the Genetic Material- 1944

1. The genetic information was thought to be contained in protein

2. Continuing the research done by Griffith in 1928, Avery worked

on the mystery of the transformation

3. Made extracts of carbohydrates, lipids, proteins, RNA and DNA

from the encapsulated strain and introduced these substances into

living non-capsulated bacteria

4. The results suggested that DNA had to be the genetic material

E. Erwin Chargaff – 1940’s

1. Chargaff's rules

a. The amount of guanine is equal to cytosine and the amount of

adenine is equal to thymine

b. The composition of DNA varies from one species to another, in

particular in the relative amounts of A, G, T, and C bases

A. The RNA Nucleotide B. Types of RNA 1. Messenger RNA a. carries the genetic code b. composed of triplets called codons c. there are 64 different codons 2. Transfer RNA a. attaches to a specific amino acid b. there are 20 different amino acids

3. Ribosomal RNA a. makes up the structure of the ribosome

C. Transcription

http://www.youtube.com/watch?v=1PSwhTGFMxs

V. Mutations to the DNA Mol A. Missense Mutation B. Nonsense Mutation