Question

Which of the following are consequences of encoding each amino acid using 3 nucleotides in the Genetic Code? (more than one) A. There are three different reading frames in a single-stranded mRNA B. tRNA anticodons contain 3 nucleotides C. There are three types of substitutions in protein coding regions (silent, missense, nonsense) D. Amino acids can be encoded by more than one codon E. There are three different stop codons F. Insertion/deletion of non-multiples of 3 bases in ORFs creates a frameshift

Answer 1

A) There are three different reading frames in a single-stranded mRNA.

The mRNA have 3 reading frames each producing a possibly distinct amino acid sequence.

B) Each tRNA contains a distinct anticodon triplet sequence that can form 3 complementary base pairs to one or more codons for an amino acid.

D) Amino acids can be encoded by more than one codon

Eg., Both codons UUC, and UUU encode Phenylalanine.

E) There are three different stop codons (UAA, UAG, UGA), which are useful for the termination of translation process.

F) Insertion/deletion of non-multiples of 3 bases in ORFs creates a frameshift resulting in a completely different translation from the original protein.