Download The discovery:DNA

DNA history
DNA History
I-Introduction
II-The discovery:DNA
III-Time line of scientists
IV-Bibliography
Introduction
What is DNA?
Deoxyribonucleic acid
What does DNA do?
the genetic instructions used in the
development and functioning of all known living
organisms.
Of what is dna established?
Double helix linked with hydrogen bonds; four bases:
adenine, guanine, thymine and cytosine; These four bases
are attached to the sugar/phosphate to form the
complete nucleotide, as shown for adenosine
monophosphate.
The discovery:DNA
.The Swiss biochemist Friedrich Miescher (18441895) discovered the nucleic acids in 1868.
His experiment:
.He collected a lot of pus of bandages at the local hospital
.He used a salt solution to wash the pus. Then he added a weak
alkaline solution to the cells lysed and nuclei precipitated out of the
solution
.So he isolated a substance called nuclein, today called DNA
Time line
1840
1900
1925
1930
1935
1940
1945
1843:
1928:
1940's:
Gregor
Frederick
Griffith
*Oswald Avery
*Erwin Chargaff
Mendel
Time line
1950
1951:
1960
Rosalind Franklin
& MauriceWilkins
1970
1980
1953:
James Watson &
Francis Crick
1990
2000
Pink=> guanine
Yellow=>cytosine
Red=> thymine
Blue=> adenine
Bibliography
*http://en.wikipedia.org/wiki/
*http://images.google.com/
*http://library.thinkquest.org/
The end