This contains information related to genetic code, contribution of scientist,table of genetic code and salient features of genetic code.

1. GENETIC CODE
Mrs. Hemanti Nitwal
PGT (Bio)
K.V. Pithoragarh

2. GENETIC CODE
 It refers to the relationship between the sequence
of nucleotides(nitrogen bases) on mRNA and the
sequence of amino acids in the polypeptide.
 The sequence of three bases determining a single
amino acid is called codon.

3. CONTRIBUTION OF SCIENTIST
 George Gamow suggested that for coding 20 amino acids
the code should be made up of 3 nucleotides . Thus, there
are 64 codons(4³=4x4x4)
 Har gobind khorana developed the chemical method in
synthesising RNA molecules with defined combinations of
bases ( homopolymers and co polymers).
 Marshal Nirenberg developed cell free system for protein
synthesis.
 Severo ochoa enzyme (polynucleotide phosphorylase)
is used to polymerise RNA with defined sequence in a
template independent manner.

4. GEORGE GAMOW HAR GOBIND
KHURANA
MARSHAL
NIRENBERG
SEVERO OCHOA

5. CODONS FOR VARIOUS AMINO ACIDS

6. SALIENT FEATURES OF GENETIC CODE
 Codon is triplet.
 61 codons code for amino acids.3 codons
(UAA,UAG,UGA) do not code for any
amino acids. They act as stop codons.
 AUG has dual functions . It codes for
methionine and act as initiator codon.
 An amino acid is coded by many codons
such codons are called degenerate
codons.

7. SALIENT FEATURES OF GENETIC CODE
Genetic code is universal
Genetic code is non over- lapping.
Genetic code is unambiguous and
specific.i.e. one codon specifies only one
amino acid.
No punctuations . Codon is read in
contiguous fashion.

8. Thank you