BIOL 3150: Chapter 7 - From DNA to Protein: How Cells Read the Genome

(Q004) Which of the following is a difference between the mechanisms of DNA polymerase and RNA polymerase?

DNA polymerase needs a base-paired 3′ −OH for a polymerization reaction to occur; RNA polymerase can polymerize two nucleotides without a base-paired 3′ −OH.

(Q022) Protein concentration can be regulated by all of the steps listed EXCEPT

DNA replication.

(Q009) What performs the function of bacterial sigma factor in eukaryotes?

general transcription factors

(Q014) Shown below is a tRNA for tryptophan. Which of the locations on the tRNA accommodates looser base-pairing rules?

site 3

(Q002) At which step of gene expression can cells amplify the number of copies of a protein made from a single gene?

both transcription and translation

(Q017) The catalytic sites for peptide bond formation during translation is found in which part of the ribosome?

large subunit RNAs

(Q013) The reading frame to use for translating an mRNA into functional protein is determined by the

location of an AUG.

(Q007) Which type of RNA is converted into protein for performing its cellular function?

mRNA

(Q020) What is the name of the complex that degrades proteins that have reached the end of their lifespan, are damaged, or are misfolded?

proteasome

(Q010) The splicing of introns out of an mRNA molecule is catalyzed by

RNA molecules that base pair with the splice sites to promote intron removal.

(Q005) Why does RNA polymerase make more mistakes than DNA polymerase?

RNA polymerase does not have proofreading activity.

(Q012) The information in an mRNA molecule is converted into protein sequence using

three consecutive bases, with no overlap between triplets.

(Q001) The process of gene expression always involves which process(es) described in the central dogma?

transcription

(Q021) The structure of a proteasome is shown below. What group is recognized by region A to indicate that the protein is marked to be eliminated?

ubiquitin

(Q011) Export of RNA from the nucleus requires the RNA to have which characteristic(s)?

5′ cap and poly-A tail

(Q019) What is the benefit of protein synthesis in polyribosomes?

More protein can be produced from a single RNA.

(Q008) Shown below is a gene with the direction of transcription noted. How does the RNA polymerase know which strand to use as a template for the RNA, and which strand would it choose in this case?

It would use the bottom strand because the promoter sets the direction and the polymerase moves from 3′ to 5′ along the template strand.

(Q016) Using the genetic code below, determine the amino acids that a polynucleotide of UC would code for.

Leu, Ser

(Q003) Which nucleic acid often base pairs with itself to fold into complex three-dimensional shapes in the cell?

RNA

(Q023) Which of the following properties could help RNA be both an information storage unit and a self-replicating molecule?

RNA can act as a template for making copies of itself.

(Q006) Which characteristic of a replicating RNA polymerase allows multiple transcripts to be made simultaneously from the same region of DNA?

The RNA transcript dissociates from the DNA template immediately once complete.

(Q024) Why is RNA thought to predate DNA in evolution?

The sugar in RNA is easier to make with the organic molecules that were present on primitive Earth.

(Q015) How do tRNAs become attached to the correct amino acid?

aminoacyl-tRNA synthetases

(Q018) What recognizes the stop codons in an mRNA?

release factor

(Q025) DNA is a better molecule for long-term storage of genetic information than RNA because

the deoxyribose sugar stabilizes DNA chains.