1. Which binding is inhibited by pactamycin?
A.Aminoacyl-tRNA to the A-site of 30S subunit
B.Initiator-tRNA to 30S/40S initiation complexes
C.Peptidyl t-RNA to the 50S subunit
D.Formation of peptide bond in P site

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2. Which of the following act as the blueprint or template for the process of protein synthesis that takes place on ribosomes?
A.rRNA
B.DNA
C.tRNA
D.mRNA

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3. Negative regulation of protein synthesis is accomplished by
A.allosteric inhibition
B.the binding of RNA polymerase to the promoter
C.the binding of a repressor to the DNA
D.the binding of a repressor to the RNA polymerase

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4. Site in the ribosome from which the tRNA donates amino acids to the growing polypeptide chain is
A.P site
B.O site
C.T site
D.A site

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5. When was the genetic code completed?
A.1958
B.1952
C.1966
D.1968

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6. Which stop codon has been found to encode selenocysteine?
A.UAA
B.UAG
C.UGA
D.AGA

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7. Which of the following is a nontranslated sequence located between the transcription and the translation start site?
A.Ending frame
B.Leader sequence
C.Trailer sequence
D.Reading frame

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