Question

phe 24 with poly- U ONO enylalanine polymerized no poly-V URI 0 0 10 20 30 40 50 60 70 80 time (min) How do the data in Figure 2.21A support linking the codon UUU to the amino acid phenylalanine? These data support that you need a codon of three nucleotides to code for 1 amino acid. When ribosomes, poly-U. RNA, and amino acids were mixed, short sequences of phenylalanine amino acids were synthesized. When ribosomes, mRNA, TRNA, and phenyialanine were mixed, short sequences of poly- were synthesized. When ribosomes, tRNA. and amino acids were mixed together in the absence of mRNA, no proteins are produced,

Answer 1

Option B is correct

When ribosome, poly U , tRNA and amino acid were mixed , short sequence of phenylalanine amino acids were synthesized.

As we can see lines in pink and green colour there is no phenylalanine polymerization present because there is no poly U sequence provided . This means poly U sequence must be present in order to carry out phenylalanine polymerization.

Rest of the above lines shows phenylalanine polymerization in presence of poly U sequence up to 7 phenylalanine amino acids which is actually short peptide.

Line at 37 is optimum temperature, shows rapid synthesis of short peptide

When temperature increases slowly ( yellow) polymerization increases slowly, reached up to 7 no of phenylalanine sequence.  

So option B is most suitable answer