Question

Do Not Reproduce

A mutation occurs that causes an adeninet
strand. The original and mutated mRNA
sequences are shown.
that causes an adenine to be replaced by a guanine in an mRNA
original and mutated mRNA strands with their associated amino acid
mRNA strand
amino acid sequence
Original
CCA UCG AAA
Pro Ser Lys
Mutation
CCA UCG AAG
Pro Ser Lys
How will this specific mutation affect protein synthesis?
A
B
Protein synthesis will stop permanently to avoid production of an incorrect protein from the
mutated strand.
The protein formed from the mutated strand will have fewer amino acids than the protein
formed from the original strand.
The protein formed from the mutated strand will be the same as the protein formed from the
original strand.
Protein synthesis will repair the mutated strand to remove the mutation before making the
protein.

Answer 1

Answer: C). The protein formed from the mutated strand will be the same as the protein formed from the original strand.

Explanation: The two protons have the same amino acid sequence therefore, the mutated protein is the same with the protein formed from the original strand. This is because the two codons AAA and AAG codes for the amino acid lysine. A phenomenon whereby an amino acid is specified by more than one codon is known as degeneracy. This does not mean that the genetic code is flawed but each codon specifies only one amino acid. The degeneracy of the codes are not uniform, some amino acids are specified by one codon, while some are specified by more than one codons. For example, methionine and tryptophan have single codons, Leucine, serine and arginine have six codons, isoleucine has three codons, alanine, glycine, and threonine have four codons.