1. If the genetic code were read in groups of four nonoverlapping nucleotides, using this nucleotide sequence, then the resulting amino acid sequence would be
A) B-D-B.
B) B-D-E.
C) D-D-D.
D) B-B-B.
E) none of the above
2. A mutant bacterium is isolated. This bacterial strain has the characteristic of very slow, "sickly" growth. You isolate mRNA from these bacteria to use in anin vitrotranslation system and note that even in vitroit is difficult to use this message and obtain protein. Of the following, which is a likely explanation for these results?
A) There may be a mutation in the ShineDelgarno sequence of the DNA, resulting in a RNA that poorly binds the ribosome.
B) In this mutant, the ribosomal subunits may not associate well enough for effective translation.
C) There may be a mutation in the ribosomal rRNA recognizing the Shine Delgarno sequence of the message.
D) This mutant may have altered tRNA molecules, such that the codon-anticodon interaction during translation is affected.
E) These bacteria may not manufacture enough translation factors for effective translation.
3. Which of the following is an example of translational regulation?
A) DNA splicing
B) protein degradation
C) protein folding
D) DNA methylation
E) mRNA degradation
4. You are working with a gene associated with an essential pathway that is necessary at two time points in an organism's lifetime. With regard to gene regulation, you would expect the gene to be
A) "activated" by particular signals (induced).
B) not constitutive.
C) associated with response to distinct events.
D) "turned off" by particular signals (repressed).
E) all of the above
5. Within a genome, an enhancer may be located
A) upstream of the gene enhanced.
B) downstream of the gene enhanced.
C) within the gene enhanced.
D) choices A, B, and C
E) both choices A and B.