GENETICS AND EVOLUTION
MOLECULAR BASIS OF INHERITANCE
|
Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
|
|
|
none of the proteins in the cell will contain phenylalanine.
|
|
|
the ribosome will skip a codon every time a UUU is encountered.
|
|
|
proteins in the cell will include lysine instead of phenylalanine at amino acid positions specified by the codon UUU.
|
|
|
the cell will compensate for the defect by attaching phenylalanine to tRNAs with lysine-specifying anticodons.
|
Detailed explanation-1: -Mutant adults exhibit many defects, including loss of neuronal cells, impaired locomotive performance, shortened lifespan and smaller organ size. At the cellular level, the mutations reduce cell proliferation and promote cell death.
Detailed explanation-2: -What would be the consequence of a mutation in a bacterial cell that produces a defective aminoacyl-tRNA synthetase that attaches a lysine instead of the normal phenylalanine to tRNAs with the anticodon AAA? The cell will compensate for the defect by attaching phenylalanine to tRNAs with lysine-specifying anticodons.
Detailed explanation-3: -The aminoacyl-tRNA synthetases recognize the correct tRNAs primarily through their overall configuration, not just through their anticodon. In addition, some aaRSs have additional RNA binding domains and editing domains that cleave incorrectly paired aminoacyl-tRNA molecules.
Detailed explanation-4: -Abstract. Aminoacyl-tRNA synthetases (ARSs) are ubiquitously expressed, essential enzymes responsible for performing the first step of protein synthesis. Specifically, ARSs attach amino acids to their cognate tRNA molecules in the cytoplasm and mitochondria.