HumGenEx4s11

Human Genetics and Medicine - BIOL 72   EXAM IV - May 19, 2011   NAME:

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Part I: [118 points] Choose the one BEST answer. Circle its letter. Read each question and all 5 choices carefully because more than one answer might seem correct at first glance. 2 pt each

1. A DNA template may (can) used to direct synthesis of
   a. RNA
   b. DNA
   c. protein
    d. a and b
   e. all of the above

2. Detectable mutations would probably occur more often if
   a. the genetic code were not degenerate
   b. DNA were single stranded
   c. the genetic code were an overlapping code
   d. a and b
    e. all of the above

3. All of the following are crucial for successful gene expression EXCEPT
   a. transcription
   b. translation
   c. folding of the protein into active/non-active 3-D forms
   d. transcription factors
    e. all are important in successful expression of a gene

4.   The part of the molecule that differs between DNA and RNA, reflected in their names, is the
   a. phosphate group
    b. sugar
   c. nitrogenous base
   d. helix
   e. double helix

5. A commonly used vector in recombinant DNA technology is a(n)
   a. enzyme
    b. plasmid
   c. virus
   d. human
   e. chromosome

6. Genes whose expression is regulated include those encoding
   a. gamma and beta globin
   b. proteins found in muscle but not in liver
   c. house-keeping proteins
    d. a and b
   e. all of the above

7. Which of the following is important for regulation of gene expression?
   a. transcription of mRNA
   b. translation of mRNA
   c. degradation of mRNA
   d. transport of mRNA
    e. all of the above

8. Misfolded proteins that can function as infectious agents are
   a. tertiary structures
    b. prions
   c. proteasomes
   d. long-chain polypeptides
   e. more than one of these

9. Which of the following is important for regulation of gene expression?
   a. transcription of mRNA
   b. translation of mRNA
   c. degradation of mRNA
   d. transport of mRNA
    e. all of the above

10. Cells found when a foreign DNA is inserted into a vector, and that vector into recipient cells are
   a. cells that lack plasmids
   b. cells that contain plasmids that do not contain a foreign gene
   c. cells that contain plasmids that have picked up a foreign gene
   d. a and b
    e. all of the above

11. Consensus sequences
   a. are present only in prokaryotes
    b. are present in both prokaryotes and eukaryotes
   c. are the promoters for transcription
   d. are found only in RNA
   e. are never found in nature; nature only approximates our calculations of “consensus”

12. Transcription is
    a. copying a single gene
   b. transporting mRNA out of the nucleus
   c. synthesizing a polypeptide
   d. gene expression
   e. completion of translation

13. Gene activity must be regulated because
   a. different cells require different products
   b. all cells in an organism carry the same genes but may do different jobs
   c. genes activity must be able to vary as the environment changes
   d. a and b
    e. all of the above

14. All of the following are true of DNA EXCEPT
   a.   every DNA nucleotide contains a sugar, a phosphate group, and a nitrogenous base
    b. short strands of DNA are contained in chromosomes inside the nucleus of a cell
   c. DNA consists of two strands of nucleic acid joined by hydrogen bonds
   d. the long strands of nucleotides are twisted into a double helix
    e. DNA can used to identify a person

15.   Cancer
   a. is genetic, but not usually inherited
   b. is caused by a loss of cell division control
   c. usually results from mutations in somatic cells
   d. may develop when an environmental trigger mutates a somatic cell
    e. all of the above

16. A clone is a
   a. bacterial colony
   b. all the offspring of a single set of parents
    c. a group of genetically identical cells or organisms
   d. a school of identical fish
   e. all of the above are examples of clones

17.   Modifications to mRNA after transcription, for the mRNA to become useable, include
   a. addition of methyl-G cap to 5’ end
   b. poly-A tail added to 3’ 3nd
   c. splicing of introns
   d. a and b
    e. all of the above

18. The bases of an RNA sequence are complementary to
   a. RNA polymerase
   b. DNA polymerase
    c. the template strand
   d. RNA
   e. DNA

19. The lagging strand of the replication fork moves in the direction of
   a. 5' –> 3'
   b. 3' –> 5'
   c. the lagging strand does not move, but it is synthesized 5' –> 3'
   d. the lagging strand does not move, but it is synthesized 3' –> 5'
    e. the lagging strand does not move; it is synthesized in a 5' –> 3' direction overall, but in 3' –> 5'fragments
    f. the lagging strand does not move; it is synthesized in a 3' –> 5' direction overall, but in 5' –> 3'fragments

20. New alleles formed by mutation(s) may result in
   a. no function
   b. new function (a protein with an altered, or new function)
   c. less function
   d. no change in function
    e. all of the above
   f. none of the above

21. In mRNA splicing
   a. introns are removed
   b. introns are retained
   c. exons are removed
   d. exons are retained
   e. b and c
    f. a and d

22. Is DNA sequence alone sufficient to regulate gene activity?
   a. YES, because promoters are specific DNA sequences
   b. YES, because trans-acting factors bind specific DNA sequences
    c. NO; we know this because all cells in an organism contain the same DNA, but different products are made in different cell types
   d. NO, because histones bind DNA randomly
   e. In some organisms, YES; in some, NO

23. If a gene causing albinism prevents the gene controlling hair color from making pigment in hair follicles, this would be an example of
   a. incomplete dominance
   b. codominance
    c. epistasis
   d. penetrance
   e. sexual dimorphism

24. Cattle can have all red hairs, all white hairs, or both red and white hairs, all controlled by the activity of a single gene. The phenotype with both red and white hairs is an example of
   a. epistasis
   b. partial dominance
    c. co-dominance
   d. incomplete penetrance
   e. complementation

25. Types of cell that can result from attempt to introduce a DNA molecule into a bacteria cell include cells
   a. that do not contain plasmids
   b. with plasmids that contain foreign genes
   c. with plasmids that do not contain foreign genes
   d. a and b
    e. all of the above

26. Ribosomal RNA (rRNA)
   a. carries the information that specifies a particular protein
   b. binds a codon at one end and a specific amino acid at the other
    c. associates with certain proteins to form a ribosome
   d. associates with certain proteins to regulate transcription
   e. is typically found in the nucleus

27. A geneticist isolated a gene for a specific trait under study and the corresponding mRNA but the mRNA is found to contain 1,000 fewer bases than the DNA sequence. Was there an error?
   a. yes, mRNA is made from a DNA template and should be the same length as the gene sequence
   b. yes, the mRNA should be longer than the DNA because bases flanking the gene are transcribed
    c. no, the final mRNA contains only exons, the introns were removed
   d. no, the mRNA was partially degraded after it was transcribed
   e. yes, eukaryotes do not produce mRNA sequences

28. An antigen
    a. is any molecule that elicits an immune response
   b. stimulates the immune system to alert T cells to produce antibodies
   c. is a type of antibody
   d. is composed of four polypeptide chains
   e. always originate outside the human body

29. A chromosome is
    a. one piece of DNA, found in nature bound to protein
   b. condensed DNA associated with proteins found in eukaryotic nuclei
   c. any condensed DNA that can be visualized
   d. a piece of DNA in eukaryotic nuclei
   e. DNA associated with proteins

30. A genetic marker
   a. is used only for mapping analysis
   b. is any gene
    c. is any DNA sequence which can be recognized
   d. is any gene which results in a recognizable phenotype
   e. can be found only in eukaryotes

31. Heterchromatin is
   a. regions of the DNA or chromosome that are available for expression in the cell
   b. regions of the DNA or chromosome that are not available for expression in the cell
   c. the dark portion of the chromosome
   d. a and c
    e. b and c

32. The weak bonds between complementary nitrogen bases are
   a. RNA bonds
    b. DNA bonds
    c. hydrogen bonds
   d. five-carbon sugar bonds
   e. sulfur bonds

33. A plasmid is a(n)
    a. extra chromosomal circular, double-stranded DNA molecule that replicates autonomously
   b. episome
   c. F-factor in E.coli
   d. DNA found in prokaryotes but not eukaryotes
   e. DNA found in cytoplasm but not in nuclei

34. Genetic engineering manipulates genetic products at the level of
   a. proteins
   b. amino acids
    c. DNA
   d. RNA
   e. mRNA

35. Transfer RNA (tRNA)
   a. carries the information that specifies a particular protein
    b. binds a codon at one end and a specific amino acid at the other
   c. associates with certain proteins to form a ribosome
   d. associates with certain proteins to regulate transcription
   e. is typically found in the nucleus

36. RNA is much less stable than DNA
   a. so, in order to keep having the RNA present, it must be made constantly
   b. some RNA is less unstable, such as tRNA and rRNA which have extensive internal base pairing
   c. as an unfortunate consequence of its structure; this presents a real problem for cells
   d. a and b
    e. all of the above

37. An allele that is expressed whenever it is present in a genome is called
   a. recessive
    b. dominant
   c. an example of the "doctrine of use and disuse"
   d. epigenesis
   e. wild type

38. The spread of cancer from its site of origin to other parts of the body is
   a. metaphase
    b. metastasis
   c. transplantation
   d. apoptosis
   e. translocation

39. The template (for transcription) strand of DNA is
   a. the same strand for all genes in a genome
   b. the same strand for all genes on a chromosome
    c. rarely both strands in the same region of DNA, but always regions of both strands are templates somewhere along the length of a chromosome in known organisms
    d. often both strands of a certain region of DNA are transcribed because some regions make sense and other regions are nonsense; the anti-parallel strands are read in opposite directions
   e. more important than the non-template strand

40. In order to find the desired cells after an experiment such as described above one would probably use
   a. selection
   b. replica plating
   c. special growth media lacking specific nutrients and/or containing antibiotics
   d. a and b
    e. all of the above

41. The DNA used in such an experiment would probably be
   a. a plasmid
   b. a vector
   c. an episome
   d. a and b
    e. all of the above

42. DNA differs from RNA in that
   a. DNA contains 2'-deoxyribose while RNA contains ribose
   b. RNA is usually single stranded while DNA is usually double-stranded
   c. DNA is much more stable under all circumstances than is RNA
   d. a and b
    e. all of the above

43. Human insulin is produced commercially in large quantities by
   a. expression of the human insulin gene in pigs
   b. a variety of techniques developed immediately following the work of Watson and Crick
   c. cows and pigs
    d. recombinant E. coli bacteria grown in large fermentation vats
   e. organic synthesis

44. If an amino acid sequence is known, one can infer the:
   a. DNA coding sequence
   b. RNA coding sequence
   c. polypeptide function
   d. a and b
    e. none of the above

45. Messenger RNA (mRNA)
    a. carries the information that specifies a particular protein
   b. binds a codon at one end and a specific amino acid at the other
   c. associates with certain proteins to form a ribosome
   d. associates with certain proteins to regulate transcription
   e. is typically found in the nucleus

46. Eukaryotes produce and use
   a. mRNA
   b. tRNA
   c. rRNA
   d. a and b
    e. all of the above

47. A gene is
    a. a sequence of DNA that instructs a cell to produce a particular protein or RNA
   b. DNA and its associated proteins
   c. the genetic material
   d. the fundamental unit of life
   e. the correspondence between specific mRNA triplets and the amino acids they specify

48. Prokaryotes (bacteria) produce and use
   a. mRNA
   b. tRNA
   c. rRNA
   d. a and b
    e. all of the above

49. Large quantities of useful products can be produced through genetic engineering involving
   a. bacteria containing recombinant plasmids
   b. yeast carrying foreign genes
   c. transgenic plants
   d. mammals producing substances in their milk
    e. all of the above

50. If a DNA sequence is known, one can infer the:
    a. RNA encoded sequence
   b. polypeptide's amino acid sequence
   c. polypeptide function
   d. a and b
   e. none of the above

51. A genetic map shows
   a. the relative distance between genes on chromosomes
   b. the location of genes on chromosomes
   c. the genetic component of key phenotypic traits
    d. a and b
   e. all of the above

52.   Humans produce and use
   a. mRNA
   b. tRNA
   c. rRNA
   d. a and b
    e. all of the above

53. Specific immunity is controlled by two classes of lymphocytes called
   a. agglutinogens and agglutinins
    b. T cells and B cells
   c. antigens and antibodies
   d. red blood cells and white blood cells
   e. none of the above

54. A gene therapy approach that has been used successfully to treat a human disorder is
    a. using gene therapy to treat severe combined immunodeficiency disease (SCID)
   b. named the polymerase chain reaction
   c. an application of genetic or linkage mapping
   d. using genetically modified foods
   e. the Human Genome Project

55. DNA polymerase
   a. joins nucleotides complementary to another (template) strand of DNA to form new DNA
   b. unwinds parental double helix
    c. stabilizes separate strands
   d. joins Okazaki fragments and seals other nicks in sugar-phosphate backbones
   e. adds short primer to template strand

56. A selectable marker could be
   a. a gene encoding an enzyme required to use a specific nutrient
   b. a gene conferring resistance to an antibiotic
   c. any identifiable DNA
    d. a and b
   e. all of the above

57. Attempting to correct certain genetic disorders through manipulating cellular DNA is called
   a. karyotype analysis
    b. gene therapy
   c. genomics
   d. risk assessment
   e. replica plating

58. Prospective parents might choose to perform genetic testing on an unborn child to
   a. abort the pregnancy if the child has a lethal disorder
   b. be prepared for what is to come
   c. possibly save the child with possible cures in vitro or at early stages of life
   d. a and b
    e. all of the above

bonus: Write a question that you studied for, and forgetful me, I neglected to ask. Answer your question. PLEASE ask yourself something you can answer well! PLEASE answer the question you actually ask. [up to 5 points awarded based on question & answer]

Part II: [10 points].   How do we manage to map genes without planned mating experiments ? Why do we want to map human genes? What type of genes would you want to support people studying, what for, and why?

Part III: [30 points] to be completed after class discussion after turning in Part I. So, the sooner everyone turns in Parts I and II, the sooner we move along.

Many approaches have been developed, and are being developed to study, assess, diagnose, screen for, manipulate, intervene in the progression of, ameliorate, and cure genetic disorders and disorders or diseases with a genetic component. Some approaches are more likely to be successful with disorders of one type than another. For each of the following pairs of disorder types, decide which would be a better candidate for the particular stated investigative or interventive approach.

Make your decision, and explain it, consider both the particulars of the approach and the disorder as you predict the likelihood of success. Take into account with regard to the approach (do not hesitate to consider other characteristics as well)
▸   the goal
▸   its limitations
▸   what one must know for its successful application

1. Government mandated and funded screening using a specific gene probe for a specific sequence:
   a relatively uncommon disorder that causes severe disability or mental insufficiency and for which there is no successful treatment except if started very early, before the onset of symptoms – or –
a relatively common disorder that can be reasonably well managed but only with a fairly restrictive diet

•   describe the technique(s) most likely to be used successfully for this purpose
•   would you support such a program; explain under what circumstances you would or would not
•   what are the costs to society of having these people left untreated?

2. gene therapy using a “shotgun” approach to insert a correct gene into a person by administering DNA directly:
A disorder caused by an allele that
(a)encodes an abnormal product – or – (b) fails to encode a required product

•   describe the technique(s) most likely to be used successfully for this purpose
•   explain which this would be more useful and effective for

3. Consider a lethal mutation that results in an unpleasant life and the need for a great deal of care, for the years that the person survives. Would you recommend (a) or (b)?
•   describe the technique(s) most likely to be used successfully for this purpose
•   explain clearly why you selected approach (a) or (b)

       a. gene therapy by inserting a correct gene into a collection of a person’s cells (that is, the cells have been taken out of the person for gene insertion in the lab), then re-introducing the cells into the person
       b. gene therapy by inserting a correct gene into a fertilized egg in vitro, then implanting the engineered embryo into the mother (or surrogate)Human Genetics and Medicine - BIOL 272   FINAL EXAM - May 19, 2011   NAME:

Part III: [30 points] Open book, open computer, open forum - please discuss this among yourselves.

Many approaches have been developed, and are being developed to study, assess, diagnose, screen for, manipulate, intervene in the progression of, ameliorate, and cure genetic disorders and disorders or diseases with a genetic component. Some approaches are more likely to be successful with disorders of one type than another. For each of the following pairs of disorder types, decide which would be a better candidate for the particular stated investigative or interventive approach.

Make your decision, and explain it, consider both the particulars of the approach and the disorder as you predict the likelihood of success. Take into account with regard to the approach (do not hesitate to consider other characteristics as well)
▸   the goal
▸   its limitations
▸   what one must know for its successful application

1. Government mandated and funded screening using a specific gene probe for a specific sequence:
   a relatively uncommon disorder that causes severe disability or mental insufficiency and for which there is no successful treatment except if started very early, before the onset of symptoms – or –
a relatively common disorder that can be reasonably well managed but only with a fairly restrictive diet

•   describe the technique(s) most likely to be used successfully for this purpose
•   would you support such a program; explain under what circumstances you would or would not
•   what are the costs to society of having these people left untreated?

2. gene therapy using a “shotgun” approach to insert a correct gene into a person by administering DNA directly:
A disorder caused by an allele that
(a)encodes an abnormal product – or – (b) fails to encode a required product

•   describe the technique(s) most likely to be used successfully for this purpose
•   explain which this would be more useful and effective for

3. Consider a lethal mutation that results in an unpleasant life and the need for a great deal of care, for the years that the person survives. Would you recommend (a) or (b)?
•   describe the technique(s) most likely to be used successfully for this purpose
•   explain clearly why you selected approach (a) or (b)

       a. gene therapy by inserting a correct gene into a collection of a person’s cells (that is, the cells have been taken out of the person for gene insertion in the lab), then re-introducing the cells into the person
       b. gene therapy by inserting a correct gene into a fertilized egg in vitro, then implanting the engineered embryo into the mother (or surrogate)