Question

QUESTION 1

1. George Beadle and Edward Tatum performed an experiment in which they made single-gene mutations in the bread mold Neurospora crassa. These mutations resulted in several Neurospora auxotrophs. Further analysis revealed specifically how the mutations affected synthesis of the amino acid in question. What was the significance of these results?

   		A single gene encodes a single protein, in the case of this experiment, an enzyme.
   		Enzymes are needed to synthesize amino acids.
   		They showed that mutations are heritable.
   		They showed that DNA is the basis of inheritance.
   		All of the above

0.5 points   

QUESTION 2

1. Which of the following is true of genes?

   		Genes consist of DNA.
   		Genes are on chromosomes.
   		Some genes encode rRNAs
   		All of the above are true

0.5 points   

QUESTION 3

1. Which of the following statements is TRUE?

   		DNA:DNA hybrids and RNA:DNA hybrids are always antiparallel.
   		DNA is replicated using the template strand as the template, but RNA is transcribed using the sense (or coding) strand as the template.
   		Both DNA and RNA polymerization require a primer.
   		Introns get spliced out of DNA and out of pre-mRNA.

0.5 points   

QUESTION 4

1. Which of the following types of RNAs are capped by 7-methyl guanosine and therefore have increased transport efficiencies and half-lives?

   		All RNAs
   		All eukaryotic RNAs
   		All mRNAs
   		Only eukaryotic mRNAs

0.5 points   

QUESTION 5

1. Which of the following types of RNAs are polyadenylated and therefore have increased transport efficiencies and half-lives?

   		Only eukaryotic mRNAs
   		All RNAs
   		All eukaryotic RNAs
   		All mRNAs

0.5 points   

QUESTION 6

1. The lac repressor in bacteria _______, and when lactose is present, the lac genes ______.

   		Activates transcription of lactose-metabolism genes; are transcribed
   		Activates transcription of lactose-metabolism genes; are NOT transcribed
   		Inhibits transcription of lactose-metabolism genes; are transcribed
   		Inhibits transcription of lactose-metabolism genes; are NOT transcribed

0.5 points   

QUESTION 7

1. There are ____ different nucleotide bases in DNA and RNA and ___ different amino acids.

   		3; 61
   		3; 21
   		4; 20
   		4; 61

0.5 points   

QUESTION 8

1. Which of the following aspects of transcription is true for bacteria but not Eukaryotes?

   		A 7-methyl guanosine cap at the 5' end of mRNA increases stability.
   		Transcription and translation may occur simultaneously.
   		Only bacteria have mRNAs
   		RNA splicing.

0.5 points   

QUESTION 9

1. Imagine that you are on a camping trip with your friends in the Adirondacks. The unusually cold, wet spring has led to an abundance of fungi, and you discover a species of fungus previously unknown to science. When you take a specimen back to the lab, you find that it secretes copious amounts of a peptide that inhibits 5’ capping of mRNA. One of your friends suggests using this new peptide as an antibiotic with which to treat bacterial infections.Why is this a bad idea?

   		Bacterial mRNAs are not capped.
   		The enzyme that caps mRNA in bacteria is different from the one in eukaryotes.
   		The antibiotic would have the side effect of preventing capping of the patient’s mRNA.
   		Peptides are not useful antibiotics.
   		Both 1st and 3rd answers above

0.5 points   

QUESTION 10

1. Which of the following has activity that is most similar to RNA Polymerase?

   		Primase
   		Helicase
   		Exonuclease
   		DNA Polymerase

Answer 1

Q1

The correct option is A single gene encodes a single protein, in the case of this experiment, an enzyme.

Q2

The correct option is all of the above are true.

Q3

The true statement is DNA:DNA hybrids and RNA:DNA hybrids are always antiparallel.

Q4

The correct option is Only eukaryotic mRNAs