Question

Characteristics of genetic code

Answer 1

Answer:

Charactrs of genetic code are as follows

1. Commaless
2. Polar
3. Specificity
4. Non ambugious
5. Diversity
6. Spcificity

Answer 2

GENETIC CODE

✏ The relationship between the sequence of amino acids in a polypeptide and nucleotide sequence of DNA or mRNA is called genetic code.

CHARACTERISTICS OF GENETIC CODE

1 . Triplet codon

✏ Genetic code is triplet code three adjacent nitrogen bases specify one amino acid.

• UGG – Tryptophan.
• AUG –Methionine

2. Non overlapping

✏ Three successive nucleotides or nitrogen bases codes for only one amino acid.

✏ Each single base is part of only one codon.

3. Commaless

✏ Genetic code does not possess punctuations.

4. Specificity or Unambiguity

✏ A codon has code for only one amino acid therefore genetic code is specific as well as unambiguous.

5. Degenerate

✏ The genetic codon are degenerate codons, they lack specificity and one amino acid has more than one code.

✏ Out of 64 codons only three are stop codon,only two codon specify a single amino acid.

✏ They are AUG for methionine and UGG for tryptophan.

• Three amino acids have six codon each.

• Five amino acid have four codons.

• One amino acid with three codon.

• Nine amino acids are specified by two codons.

6. Universal

✏ Genetic code is universal, a given codon specifies the same amino acid in the protein synthesising system of all organisms.

7. Initiation codon/ start codon

✏ The codons AUG and GUG for methionine and valine act as start signal, they initiate the synthesis of polypeptide chain (Dual function).

✏ In eukaryotes, methionine is the first amino acid and formylmethionine in prokaryotes.

8. Termination codon/Non sense/Stop codon :-

✏ There are three stop codons (UAA,UGA,UAG).

✏ Do not specify any amino acid but signals at the end of the message.