Question

A mutant bacterial cell has a defective aminoacyl synthetase that attaches a lysine to tRNAs with the anticodon AAA instead of the normal phenylalanine. The consequence of this for the cell will be that:_____________a) none of the proteins in the cell will contain phenylalanine.b) proteins in the cell will include lysine instead of phenylalanine at amino acid positions specified by the codon UUU.c) the cell will compensate for the defect by attaching phenylalanine to tRNAs with lysine-specifying anticodons.d) the ribosome will skip a codon every time a UUU is encountered.e) none of the options will occur; the cell will recognize the error and destroy the tRNA.

Answer 1

Answer:

Proteins in the cell will include lysine instead of phenylalanine at amino acid positions specified by the codon UUU.

Explanation:

Mutation may be defined as the sudden or heritable change in the genetic sequence of the organisms. The mutation can change the phenotype and genotype of the organisms.

The AAA codes for the lysine. The mutation attaches the anticodon AAA instead of normal phenylalanine. The aminonacids AAA will code for the lysine and no phenylalanine is observed in the cell as phenylalanine is coded by UUU and not by AAA.

Thus, the correct answer is option (b).