ch 12 gene

Which of the following is not a characteristic of the genetic code?

• The genetic code is universal.

• The genetic code is overlapping.

• The genetic code is degenerate.

• The genetic code is commaless.

• The genetic code is unambiguous.

The genetic code is said to be triplet, meaning that there ________.

• the three bases in mRNA that code for an animo acid

• no

A class of mutations that results in multiple contiguous (side-by-side) amino acid changes in proteins is probably caused by which one of the following types of mutations?

• frameshift

• transversion

• transition

• base analog

• recombinant

When scientists were attempting to determine the structure of the genetic code, Crick and coworkers found that when three base additions or three base deletions occurred in a single gene, the wild-type phenotype was sometimes restored. These data supported the hypothesis that

• there are three amino acids per base

• the code contains internal punctuation

• AUG is the initiating triplet

• the code is overlapping

• the code is triplet

How many five letter codons could be made from a four nucleotide code?

• 16

• 64

• 256

• 54

• 1024

Significant in the deciphering of the genetic code was the discovery of the enzyme polynucleotide phosphorylase. What is this enzyme used for?

• manufacture of synthetic RNA for cell-free systems

• ribosomal translocation

• peptide bond formation

• production of ribosomal proteins

• degradation of RNA

In 1964, Nirenberg and Leder used the triplet binding assay to determine specific codon assignments. A complex of which of the following components was trapped in the nitrocellulose filter?

• ribosomes and DNA

• free tRNAs

• charged tRNA, RNA triplet, and ribosome

• uncharged tRNAs and ribosomes

• sense and antisense strands of DNA

What is the name given to the three bases in a messenger RNA that bind to the anticodon of tRNA to specify an amino acid placement in a protein?

• protein

• anti-anticodon

• cistron

• rho

• codon

In a mixed heteropolymer experiment A and C are added in a ratio of 1A:5C. What would be the frequency of getting an ACA triplet?

• A) 2.3%

• B) 6.9%

• C) 11.6%

• D) 57.9%

• E) 34.8%

What would be the probability of occurrence of the triplet GCG in a heteropolymer experiment with a ratio of 2G:1C?

• A) 14.8%

• B) 67.2%

• C) 50.1%

• D) 25.6%

• E) 10.5%