1. Chapter 17
From Gene to Protein

2. A mutation results in a defective enzyme a. In the following simple metabolic pathway, what would be a consequence of that mutation?
enzyme a
enzyme b
a b c
an accumulation of A and no production of B and C
an accumulation of A and B and no production of C
an accumulation of B and no production of A and C
an accumulation of B and C and no production of A
an accumulation of C and no production of A and B
Answer: 1
Source: Barstow - Test Bank for Biology, Seventh Edition, Question #3

3. If proteins were composed of only 12 different kinds of amino acids, what would be the smallest possible codon size in a genetic system with four different nucleotides? 1 2 3 4 12
Answer: 2
Source: Barstow - Test Bank for Biology, Seventh Edition, Question #9

4. A portion of the genetic code is UUU = phenylalanine, GCC = alanine, AAA = lysine, and CCC = proline. Assume the correct code places the amino acids phenylalanine, alanine, and lysine in a protein (in that order). Which of the following DNA sequences would substitute proline for alanine?
AAA-CGG-TTA
AAT-CGG-TTT
AAA-CCG-TTT
AAA-GGG-TTT
AAA-CCC-TTT
Answer: 4
Source: Barstow - Test Bank for Biology, Seventh Edition, Question #20

5. A particular triplet of bases in the coding sequence of DNA is AAA
A particular triplet of bases in the coding sequence of DNA is AAA. The anticodon on the tRNA that binds the mRNA codon is
TTT.
UUA.
UUU.
AAA.
either UAA or TAA, depending on wobble in the first base.
Answer: 4
Source: Barstow - Test Bank for Biology, Seventh Edition, Question #39

6. tRNA Anticodon Amino Acid
A part of an mRNA molecule with the following sequence is being read by a ribosome: 5' CCG-ACG 3' (mRNA). The following activated transfer RNA molecules are available. Two of them can correctly match the mRNA so that a dipeptide can form.
tRNA Anticodon
Amino Acid
GGC
Proline
CGU
Alanine
UGC
Threonine
CCG
Glycine
ACG
Cysteine
CGG
The dipeptide that will form will be
cysteine-alanine.
proline-threonine.
glycine-cysteine.
alanine-alanine.
threonine-glycine.
Answer: 2
Source: Barstow - Test Bank for Biology, Seventh Edition, Question #42

7. This figure represents tRNA that recognizes and binds a particular amino acid (in this instance, phenylalanine). Which of the following triplets of bases on the mRNA strand codes for this amino acid?
UGG
GUG
GUA
UUC
CAU
Answer: 4
Source: Barstow - Test Bank for Biology, Seventh Edition, Question #44

8. Each of the following is a modification of the sentence THECATATETHERAT. A. THERATATETHECAT B. THETACATETHERAT C. THECATARETHERAT D. THECATATTHERAT E. CATATETHERAT Which of the above is analogous to a frameshift mutation? A B C D E
Answer: 4
Source: Barstow - Test Bank for Biology, Seventh Edition, Question #68

9. Each of the following is a modification of the sentence THECATATETHERAT. A. THERATATETHECAT B. THETACATETHERAT C. THECATARETHERAT D. THECATATTHERAT E. CATATETHERAT Which of the above is analogous to a single substitution mutation? A B C D E
Answer: 3
Source: Barstow - Test Bank for Biology, Seventh Edition, Question #69

10. What is the relationship among DNA, a gene, and a chromosome?
A chromosome contains hundreds of genes, which are composed of protein.
A chromosome contains hundreds of genes, which are composed of DNA.
A gene contains hundreds of chromosomes, which are composed of protein.
A gene is composed of DNA, but there is no relationship to a chromosome.
A gene contains hundreds of chromosomes, which are composed of DNA.
Answer: 2
Source: Barstow - Test Bank for Biology, Seventh Edition, Question #75

11. A biologist inserts a gene from a human liver cell into the chromosome of a bacterium. The bacterium then transcribes this gene into mRNA and translates the mRNA into protein. The protein produced is useless. The biologist extracts the protein and mature mRNA that codes for it. When analyzed you would expect which of the following results? *
the protein and the mature mRNA are longer than in human cells
the protein and mature mRNA are shorter than expected
the protein is longer and the mRNA is shorter than expected
the protein is shorter and the mRNA is longer than expected
Answer: 1
Source: Campbell/Reece - Biology, Seventh Edition, EOC Process of Science Question
Discussion Notes for the Instructor
There are several questions which can be asked to guide the discussion of this question, including:
What are the differences between the way the genetic information in prokaryotes and eukaryotes is packaged?
How do transcription and translation differ in prokaryotes and eukaryotes?
Using these questions as an outline, discussion of the choices might look like this:
Choice A, correct
Choice B, eukaryotes contain introns that are normally removed after transcription. In bacteria these introns would not be removed and then subsequently would be translated
Choice C, the protein would not be expected to be longer if the mRNA is shorter
Choice D, while it is possible for the protein to be shorter, owing to a termination sequence being found in what was an intron, this is unlikely.

12. How is the template strand for a particular gene determined?
It is the DNA strand that runs from the 5' → 3' direction.
It is the DNA strand that runs from the 3' → 5' direction.
It depends on the orientation of RNA polymerase, whose position is determined by particular sequences of nucleotides within the promoter.
It doesn’t matter which strand is the template because they are complementary and will produce the same mRNA.
The template strand always contains the TATA box.
Answer: 3
Source: Taylor - Student Study Guide for Biology, Seventh Edition, Test Your Knowledge Question #5

13. Bacterial Genetic Recombination:
Transduction
Transformation
Conjugation
Mutation

19. A researcher lyses a cell that contains nucleic acid molecules and capsid units of tobacco mosaic virus (TMV). The cell contents are left in a covered test tube overnight. The next day this mixture is sprayed on tobacco plants. Which of the following would be expected to occur?
The plants would develop some but not all of the symptoms of the TMV infection.
The plants would develop symptoms typically produced by viroids.
The plants would develop the typical symptoms of TMV infection.
The plants would not show any disease symptoms.
The plants would become infected, but the sap from these plants would be unable to infect other plants.
Answer: 3
Source: Barstow - Test Bank for Biology, Seventh Edition, Question #3

20. A mutation that inactivates the regulator gene of a repressible operon in an E. coli cell would result in
continuous transcription of the structural gene controlled by that regulator.
complete inhibition of transcription of the structural gene controlled by that regulator.
irreversible binding of the repressor to the operator.
inactivation of RNA polymerase.
both B and C.
Answer: 1
Source: Barstow - Test Bank for Biology, Seventh Edition, Question #52

21. A mutation that makes the regulatory gene of an inducible operon nonfunctional would result in
continuous transcription of the operon's genes.
reduced transcription of the operon's genes.
accumulation of large quantities of a substrate for the catabolic pathway controlled by the operon.
irreversible binding of the repressor to the promoter.
overproduction of cAMP receptor protein.
Answer: 1
Source: Campbell/Reece - Biology, Seventh Edition, EOC Self-Quiz Question #7

22. A mutation that renders nonfunctional the product of a regulatory gene for an inducible operon would result in *
continuous transcription of the genes of the operon.
complete blocking of the attachment of RNA polymerase to the promoter.
irreversible binding of the repressor to the operator.
no difference in transcription rate when an activator protein was present.
negative control of transcription.
Answer: 1
Source: Taylor - Student Study Guide for Biology, Seventh Edition, Test Your Knowledge Question #25
Discussion Notes for the Instructor
There are several questions which can be asked to guide the discussion of this question, including:
What does the regulatory gene in the operon produce?
In an inducible operon is this product normally active or inactive?
Using these questions as an outline, discussion of the choices might look like this:
Choice A, correct
Choice B, there would be no repressor molecule and therefore nothing to block RNA polymerase
Choice C, there would be no repressor molecule
Choice D, normally the repressor molecule would still be blocking transcription, so there would be a difference in rate.
Choice E, similar to Choice C

26. PCR
Southern Hybridization