Single Choice

Choose the correct answer from the alternatives given : An organism uses 20 amino acids while its DNA is made up of 6 types of nitrogenous bases. What would be the minimum size of a codon?

A6
B4
C3
D2
Correct Answer

Solution

As there are 20 amino acids thus there must be at least 20 unique combinations of the bases. If the code is singlet i.e., consists of only one base then possible codons can be (6)1=6, which is far less than the required number i.e., 20. If the code is doublet (made up of combination of two bases) then the possible codons can be (6)2=36. 36 is sufficient (even more) than the required number. Here some amino acid could be coded by more than one codon and some codons will function as start and stop codons.
So, the correct answer is ''2'.

SIMILAR QUESTIONS

Genetics

Select the correct option regarding genetic code of Glycine.

Genetics

Match column I with column II and select the correct option from the-given codes. Column I (Codons) Column II (Translated amino acid) A. UUU (i) Serine B. GGG (ii) Methionine C. UCU (iii) Phenylalanine D. CCC (iv) Glycine E. AUG (v) Proline

Genetics

Choose the correct answer from the alternatives given : Read the following statements. (i) One codon codes for only one amino acid. (ii) Some amino acids are coded by more than one codon. (iii) The, sequence of triplet nitrogenous bases in DNA or mRNA corresponds to the amino acid sequence in the polypeptide chain. Give suitable terms for the characteristics of genetic code as per the above statements.

Genetics

One of the following is true with respect to AUG

Genetics

Which of the following Is correct regarding genetic code?

Genetics

Find the sequence of binding of the following amino acyl-tRNA complexes during translation of an mRNA transcribed by a DNA segment having the base sequence 3'TACATGGGTCCG5'. Choose the answer showing the correct order of alphabets.

Genetics

In an in vitro translation experiment, poly(UC) RNA template produced poly(Ser-Leu), while poly(AG) RNA template produced poly (Arg-Glu) polypeptide. Which one of the following options represents correct interpretations of the codons assignments for Ser, Leu, Arg, and Glu.

Genetics

A protein with $$100$$ amino acid residues has been translated based on triplet genetic code. Had the genetic code been quadruplet, the gene that codes for the protein would have been.

Genetics

One of the following is true with respect to AUG

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