In the triplet binding technique, radioactivity remains on the filter when the amino acid corresponding to the codon is labeled. Explain the rationale for this technique.

What is the role of codons UAA, UGA, and UAG in translation? What events occur when one of these codons appears at the A site of the ribosome?

How many different proteins, each with a unique amino acid sequence, can be constructed that have a length of five amino acids?

Predict the amino acid sequence produced during translation by the following short hypothetical mRNA sequences (note that the second sequence was formed from the first by a deletion of only one nucleotide):

Sequence 1: 5'-AUGCCGGAUUAUAGUUGA-3'

Sequence 2: 5'-AUGCCGGAUUAAGUUGA-3'

What type of mutation gave rise to sequence 2?

Third-base wobble allows some tRNAs to recognize more than one mRNA codon. Based on this chapter's discussion of wobble, what is the minimal number of tRNA molecules necessary to recognize the following amino acids?

Isoleucine

Third-base wobble allows some tRNAs to recognize more than one mRNA codon. Based on this chapter's discussion of wobble, what is the minimal number of tRNA molecules necessary to recognize the following amino acids?

Arginine

Third-base wobble allows some tRNAs to recognize more than one mRNA codon. Based on this chapter's discussion of wobble, what is the minimal number of tRNA molecules necessary to recognize the following amino acids?

Leucine

A short RNA molecule was isolated that demonstrated a hyperchromic shift, indicating secondary structure. Its sequence was determined to be

   5'-AGGCGCCGACUCUACU-3'

If the molecule were an internal part of a message, what amino acid sequence would result from it following translation?