Explore BrainMass

Explore BrainMass

    Hypothesis for single start codon and triple stop codon

    This content was COPIED from BrainMass.com - View the original, and get the already-completed solution here!

    I need help with this question. I just need some steps in figuring it out Im totally lost Recall that mRNA has one start codon and three codons. based on what you know about process of gene expression, hypothesize why it would be benefecial to have only one start codon but three stop codons in this process.

    © BrainMass Inc. brainmass.com May 20, 2020, 7:41 pm ad1c9bdddf

    Solution Preview

    The genetic code establishes which amino acids will be added to a growing polypeptide. It also specifies for the initiation of translation by the start codon (UAG) and termination of translation by the stop codons (UAG, UGA, and UAA). There is a degeneracy in the genetic code whereby an amino acid may correspond to more than one codon. With 4 bases and three positions there are 64 possible codons, but there are only 20 amino acids.

    The ability for more than one codon to specific an amino acid allows for the system to accommodate a certain amount of somatic mutations. For example, serine is specified by the codons UCA, UCG, UCC, UCU, AGU, AGC. If the codon UCA is mutated to UCU the amino acid is preserved. Serine residues main be modified via phosphorylation as a means to regulate protein activity. In cases ...

    Solution Summary

    Several paragraphs developing a hypothesis as to why there is only 1 start codon but 3 stop codons. Web references provided.