You have discovered an alien life-form that surprisingly uses DNA as its genetic material, makes RNA from DNA, and reads the information from RNA to make protein using ribosomes and tRNAs, which read triplet codons.Because it is your job to decipher the genetic code for this alien, you synthesize some artificial RNA molecules and examine the protein products produced from these RNA molecules in a cell-free translation system using purified alien tRNAs and ribosomes.You obtain the results shown in Table 7-48. $\begin{array}{c|c} \text { Message } & \text { Peptides produced } \\ \hline \text { poly UA } & \text {... Tyr-Cys-Tyr-Cys ... } \\ \hline \text { poly UC } & \text {... Phe-Lys-Phe-Lys .... }\\ \text { poly UAC } & \ldots \text { lle-lle-lle-lle ... } \\ & +\\ &\text {... Ser-Ser-Ser-Ser... } \\ &+ \\ &\text {... Pro-Pro-Pro-Pro ... }\\ \hline\text { poly UCA } & \text {... Ala-Ala-Ala-Ala ... } \\ & +\\ &\text { ... His-His-His-His...}\\ &+\\ &\text { ... Val-Val-Val-Val...}\\ \hline\text { poly AUA } & \ldots \text { Arg-Arg-Arg-Arg ... } \\ & +\\ &\text { ... Glu-Glu-Glu-Glu... }\\ &+\\&\text { ... Tyr-Tyr-Tyr-Tyr ... } \end{array}$ Table 7-48 From this information, which of the following peptides can be produced from poly UAUC?

A) Ile-Phe-Val-Tyr B) Tyr-Ser-Phe-Ala C) Ile-Lys-His-Tyr D) Cys-Pro-Lys-Ala A) Ile-Phe-Val-Tyr B) Tyr-Ser-Phe-Ala C) Ile-Lys-His-Tyr D) Cys-Pro-Lys-Ala

A strain of yeast translates mRNA into protein inaccurately.Individual molecules of a particular protein isolated from this yeast have variations in the first 11 amino acids compared with the sequence of the same protein isolated from normal yeast cells, as listed in Figure 7-33.What is the most likely cause of this variation in protein sequence? \(\begin{array}{c} \begin{array}{lll} \text {normal sequence}\\ \\ \text {variants}\\ \\ \\ \\ \\ \\ \end{array} \begin{array}{lll} \text {Met}\\ \\ \text {Met}\\ \text {Met}\\ \text {Met}\\ \text {Met}\\ \text {Met}\\ \text {Met} \end{array} \begin{array}{lll} \text {Thr}\\ \\ \text {Thr}\\ \text {Thr}\\ \text {Thr}\\ \text {Thr}\\ \text {Thr}\\ \text {Thr} \end{array} \begin{array}{lll} \text {Ala}\\ \\ \text {Ala}\\ \text {Ala}\\ \text {Ala}\\ \text {Ala}\\ \text {Ala}\\ \text {Ala} \end{array} \begin{array}{lll} \text {Ile}\\ \\ \text {Ala}\\ \text {Gly}\\ \text {val}\\ \text {Ile}\\ \text {Ile}\\ \text {Ile} \end{array} \begin{array}{lll} \text {Val}\\ \\ \text {Val}\\ \text {Val}\\ \text {Val}\\ \text {Val}\\ \text {Val} \\ \text {Va} \end{array} \begin{array}{lll} \text {Ser}\\ \\ \text {Ser}\\ \text {Ser}\\ \text {Ser}\\ \text {Ser}\\ \text {Ser}\\ \text {Ser} \end{array} \begin{array}{lll} \text {Asn}\\ \\ \text {Asn}\\ \text {Asn}\\ \text {Asn}\\ \text {Asn}\\ \text {Asn}\\ \text {Asn} \end{array} \begin{array}{lll} \text {Thr}\\ \\ \text {Thr}\\ \text {Thr}\\ \text {Thr}\\ \text {Thr}\\ \text {Thr}\\ \text {Thr} \end{array} \begin{array}{lll} \text { Gln}\\ \\ \text { Gln } \\ \text { Gln } \\ \text { Gln } \\ \text { Gln } \\ \text { Gln } \\ \text { Gln } \end{array} \begin{array}{lll} \text { Ile}\\ \\ \text { Ile}\\ \text { Ile}\\ \text { Ile}\\ \text { Ala}\\ \text { Gly}\\ \text { Val} \end{array} \begin{array}{lll} \text {Lys}\\ \\ \text {Lys}\\ \text {Lys}\\ \text {Lys}\\ \text {Lys}\\ \text {Lys}\\ \text {Lys}\\ \end{array} \end{array}\) Figure 7-33 $\text { The Genetic Code }$ \(\begin{array}{|l|l|l|l|l|} \hline & \text { U } & \text { C } & \text { A } & \text { G } \\ \hline &\text { UUU Phe (F) } & \text { UCU Ser (S) } & \text { UAU Tyr (Y) } & \text { UGU Cys (C) } \\ &\text { UUC - } & \text { UCC - } & \text { UAC - } & \text { UGC - } \\ \text { U } &\text { UUA Leu (L) } & \text { UCA -- } & \text { UAA Stop } & \text { UGA Stop } \\ &\text { UUG - } & \text { UCG - } & \text { UAG Stop } & \text { UGG Trp (W) } \\ \hline &\text { CUU Leu (L) } & \text { CCU Pro (P) } & \text { CAU His (H) } & \text { CGU Arg (R) } \\ &\text { CUC - } & \text { CCC - } & \text { CAC - } & \text { CGC - } \\ \text { C}&\text { CUA - } & \text { CCA - } & \text { CAA Gin (Q) } & \text { CGA - } \\ &\text { CUG }- & \text { CCG }- & \text { CAG }- & \text { CGG }- \\ \hline &\text { AUU Ile (I) } & \text { ACU Thr (T) } & \text { AAU Asn (N) } & \text { AGU Ser (S) } \\ &\text { AUC - } & \text { ACC - } & \text { AAC - } & \text { AGC - } \\ \text { A}&\text { AUA - } & \text { ACA - } & \text { AAA Lys (K) } & \text { AGA Arg (R) } \\ &\text { AUG Met (M) } & \text { ACG - } & \text { AAG - } & \text { AGG - } \\ \hline &\text { GUU Val (V) } & \text { GCU Ala (A) } & \text { GAU Asp (D) } & \text { GGU Gly (G) } \\ &\text { GUC - } & \text { GCC - } & \text { GAC - } & \text { GGC - } \\ \text { G}&\text { GUA - } & \text { GCA - } & \text { GAA Glu (E) } & \text { GGA - } \\ &\text { GUG - } & \text { GCG - } & \text { GAG - } & \text { GGG - } \\ \hline \end{array}\) Table 7-29

A) a mutation in the DNA coding for the protein B) a mutation in the anticodon of the isoleucine-tRNA (tRNAIle) C) a mutation in the isoleucyl-tRNA synthetase that decreases its ability to distinguish between different amino acids D) a mutation in the isoleucyl-tRNA synthetase that decreases its ability to distinguish between different tRNA molecules A) a mutation in the DNA coding for the protein B) a mutation in the anticodon of the isoleucine-tRNA (tRNAIle) C) a mutation in the isoleucyl-tRNA synthetase that decreases its ability to distinguish between different amino acids D) a mutation in the isoleucyl-tRNA synthetase that decreases its ability to distinguish between different tRNA molecules

A) are translated into snRNPs. B) are important for producing mature mRNA transcripts in bacteria. C) are removed by the spliceosome during RNA splicing. D) can bind to specific sequences at intron-exon boundaries through complementary base-pairing. A) are translated into snRNPs. B) are important for producing mature mRNA transcripts in bacteria. C) are removed by the spliceosome during RNA splicing. D) can bind to specific sequences at intron-exon boundaries through complementary base-pairing.