Microbiology and Immunology

WORLD OF MICROBIOLOGY AND IMMUNOLOGY DNA (deoxyribonucleic acid)

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Diagram depicting semiconservative DNA replication.

as that for red hair), while another sequence, such as G-C-T-

C-T-C-G...etc., might code for a different kind of protein

(such as that for blonde hair). Watson and Crick themselves

contributed to the deciphering of this genetic code, although

that process was long and difficult and involved the efforts of

dozens of researchers over the next decade.

Watson and Crick had also considered, even before

their March 7th discovery, what the role of DNA might be in

the manufacture of proteins in a cell. The sequence

that they outlined was that DNA in the nucleus of

a cell might act as a template for the formation of

a second type of nucleic acid, RNA(ribonucleic

acid). RNA would then leave the nucleus, emigrate

to the cytoplasmand then itself act as a template

for the production of protein. That theory, now

known as the Central Dogma, has since been

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