Name___________________________ Date____________________Genetics Regents Review

A) hybridization B) nondisjunctionC) polyploidy D) segregation

1. The chromosomes of a person with a geneticdisorder are shown in the diagram below.

This genetic disorder resulted from

2. Base your answer to the following question onthe diagram of paired homologouschromosomes shown below and on yourknowledge of biology.

A) screening B) chromatographyC) karyotyping D) grafting

Which technique was used to organize thechromosomes as shown in the diagram?

3. Base your answer to the following question on"the diagram below of the chromosomes froma human cell and on your knowledge ofbiology.

"

A) genetic counselingB) amniocentesisC) urine analysisD) cloning

Which procedure can be performed duringfetal development to detect the chromosomaldisorder illustrated by the diagram?

A) a 3n individualB) an individual with Down syndromeC) a normal diploid individualD) a monoploid, colorblind individual

4. The diagram below illustrates fertilization in ahuman.

Which type of individual might result fromthis fertilization?

A)

B)

C)

D)

5. Which diagram correctly illustrates the fusionof normal gametes that will most likelyproduce a human male?

A) temperature, onlyB) asexual reproductionC) the environmentD) pH, only

6. The diagram below represents geneticmaterial.

The expression of the section labeled X maybe modified by

A) receptor moleculesB) carbohydratesC) enzymesD) starch molecules

7. A laboratory technique is represented in thediagram below. Letter A represents a process.

Which specific chemicals are needed tosuccessfully carry out the process shown at A?

A) 15% B) 30%C) 35% D) 85%

8. In a DNA sample, 15% of the bases arethymine (T). What percentage of the bases inthis sample are adenine (A)?

A) segment 1, only B) segment 3, onlyC) segments 2 and 3 D) segments 2 and 4

9. Four different segments of a DNA molecule are represented below.

There is an error in the DNA molecule in

A) sugar moleculesB) molecular basesC) enzymesD) proteins

10. The diagram below represents a portionDNA molecule.

The letters represent different types ofA) protein composed of folded chains of

base subunitsB) biological catalystC) part of a gene for a particular traitD) chromosome undergoing a mutation

11. The diagram below represents a structurefound in most cells.

The section labeled A in the diagram is mostlikely a

A) four types of base subunitsB) folded chains of glucose moleculesC) twenty different kinds of amino acidsD) complex, energy-rich inorganic

molecule

12. The diagram below represents levels oforganization within a cell of a multicellularorganism.

The level represented by X is composed of

A) It is the template for the replication ofgenetic information.

B) Organic catalysts are made up of thesemolecules.

C) It is different in each cell of anorganism.

D) Cell membranes contain many of thesemolecules.

13. The molecule represented below is found inliving things.

Which statement describes one characteristicof this molecule?

A) 15% B) 35%C) 70% D) 85%

14. If 15% of a DNA sample is made up ofthymine, T, what percentage of the sample ismade up of cytosine, C?

A) cellulose – polypeptidesB) DNA – nucleotidesC) protein – monosaccharidesD) fat – disaccharides

15. Which molecule is correctly paired with itsbuilding blocks?

A)

B)

C)

D)

16. The parts of a DNA nucleotide are indicatedin the chart below by letters A , B , and C ,An X indicates which chemical elements arepresent in each part.

Which diagram best represents a DNAnucleotide.

A) provide an exact copy of the geneticcode

B) ensure genetic variation in a speciesC) synthesize cellular proteinsD) produce antibodies to combat disease

17. The process represented in the diagrambelow occurs in many cells.

The main function of this process is to

A) All the cells have identical DNA.B) The DNA of the fertilized egg differs from the DNA of all the other cells.C) The DNA of the fertilized egg differs from some, but not all, of the other cells.D) Only the fertilized egg contains DNA.

18. The diagram below represents a process that occurs during normal humandevelopment.

Which statement is correct regarding the cells and DNA?

A) carbohydrate B) geneC) ribosome D) chromosome

19. The diagram below shows some of the stepsin protein synthesis?

The section of DNA being used to make thestrand of mRNA is known as a

A) recombination B) fertilizationC) replication D) mutation

20. Which nuclear process is represented below?

A) have some similar DNA basesequences.

B) can use carbon dioxide to makeproteins.

C) digest proteins into simple sugars.D) contain certain pathogenic microbes.

21. A certain protein is found in mitochondria,chloroplasts, and bacteria. This providesevidence that plants and bacteria

A) AGC B) TCGC) TAC D) GAT

22. In the diagram below, strands I and IIrepresent portions of a DNA molecule.

Strand II would normally include

Base your answers to questions 23 through 25 on the diagram below of a DNA molecule andon your knowledge of biology.

A) phosphateB) deoxyribose sugarC) ribose sugarD) base

23. Structure 3 represents a

A) Structure 1 is hydrolyzed.B) A chemical bond is broken in region 2.C) Structure 3 is synthesized.D) Proteins are formed in region 2.

24. Which activity occurs in the process ofreplication?

A) C-A-T-G B) A-C-G-TC) A-C-T-G D) G-C-T-A

25. The base sequence of strand X is

A) cell reproductionB) meiosisC) mutationD) gene replication

26. The diagram below represents one processthat might occur in cells.

Which process is represented in thediagram?

A) 1 B) 2 C) 3 D) 4

27. The diagram below can be used to illustrate cellular changes.

Which row of terms in the chart below best completes the diagram?

A) (1) B) (2) C) (3) D) (4)

28. The diagram below shows a normal gene sequence and three mutated sequences of asegment of DNA.

Which correctly identifies the cause of each type of mutation?

A) The molecule will be converted into aninorganic compound.

B) The amino acid sequence may bealtered during protein synthesis.

C) The chromosome number will decreasein future generations.

D) The chromosome number may increasewithin the organisms.

29. The diagram below represents a portion of atype of organic molecule present in the cellsof organisms.

What will most likely happen if there is achange in the base sequence of thismolecule?

A) The amino acid sequence would be shorter.B) One amino acid in the sequence would change.C) The amino acid sequence would remain unchanged.D) More than one amino acid in the sequence would change.

30. Base your answer to the following question on the portion of the mRNA codon chartand information below.

How would the amino acid sequence produced by the mutant strand (series II)compare to the amino acid sequence produced by series I?

A) codon B) geneC) polypeptide D) nucleotide

31. A sequence of three nitrogenous bases in amessenger-RNA molecule is known as a

A) adenine B) uracilC) cytosine D) guanine

32. Which base is normally used in the synthesisof RNA but not in the synthesis of DNA?

A) A-A-U B) G-G-TC) T-T-C D) U-U-A

33. If a portion of a messenger RNA moleculecontains the base sequence A-A-U, thecorresponding transfer RNA base sequenceis

A) C-A-A-G-G-U B) G-T-T-C-C-AC) G-U-U-C-C-A D) C-A-A-G-G-T

34. What is the complementary messenger-RNAsequence for the DNA sequence shownbelow?

A) DNA, onlyB) Messenger RNA, onlyC) Transfer RNA, onlyD) DNA, messenger RNA, and transfer

RNA

35. Which of the following nucleic acids arecomposed of nucleotides?

A) B)

C) D)

36. Which sequence best represents the relationship between DNA and the traits of anorganism?

37. Base your answer to the following question on "the diagram below, which represents asequence of events in a biological process that occurs within human cells and on yourknowledge of biology.

"

A) they are usually composed of genetic informationB) they are usually involved in the synthesis of antibioticsC) they are usually composed of amino acidsD) they are usually involved in the diffusion of oxygen into the cell

Molecules B, C, and D are similar in that they are usually

A) DNA is produced from proteinabsorbed by the cell.

B) Protein is composed of DNA that isproduced in the cell.

C) DNA controls the production of proteinin the cell.

D) Cells make DNA by digesting protein.

38. Which statement best expresses therelationship between the three structuresrepresented below?

A) excess energy for step 2 prevented the conversion of substance B to substance CB) an excess of enzyme X was present, resulting in a decrease in the production of

substance BC) nuclear DNA was altered resulting in the cell being unable to make enzyme YD) a mutation occurred causing a change in the ability of the cell to use substance C

39. The diagram below represents the chemical pathway of a process in a human livercell.

A particular liver cell is unable to make substance C . One possible explanation for theinability of this cell to make substance C is that

Base your answers to questions 40 through 43 on "the diagram below, which represents somecomponents involved in cellular proteinsynthesis, and on your knowledge of Biology.

"

A) DNA B) RNAC) dipeptides D) amino acids

40. The type of molecule represented at A issynthesized according to a template found in

A) 1 B) 6 C) 3 D) 9

41. How many codons are located on themessenger RNA molecule in the diagram?

A) nuclear DNAB) cytoplasmic DNAC) ribosomal RNAD) transfer RNA

42. What does Structure B represent a moleculeof?

A) a polypeptideB) a polysaccharideC) DNAD) RNA

43. Molecules C, D, and E will combine toform part of

Base your answers to questions 44 through 46 on "the diagram below, which represents some biochemical reactions involved in a cellularprocess.

"

A) 1 B) 2 C) 3 D) 4

44. The molecule coded directly from DNA is represented by number

A) a peptide bond B) a hydrogen bondC) an ionic bond D) a carboxyl bond

45. What is the bond labeled 5 known as?

A) glucose B) glycogen C) a fatty acid D) a protein

46. What is an example of a molecule produced by this type of process?

47. Base your answer to the following question on "the diagram below, which contains arrows representing different processes occurringin a cell.

"

A) a strand of DNAB) two complementary strands of DNAC) a strand of RNAD) a chain of amino acids

What is the product of process 3?

A) A B C DB) B C A DC) C B A DD) D B A C

48. Four stages in the production of proteinmolecules in a cell are listed below.

A – Transfer RNA molecules bring aminoacidsto the ribosomeB – DNA molecules serve as templates formessenger RNA molecules.C – Messenger RNA molecules move toribosomes.D – Polypeptides are formed on ribosomes.

Which sequence best represents the correctorder of these stages?

Base your answers to questions 49 and 50 on the diagram below of two processes inthe synthesis of proteins and on your knowledge of biology.

A) mitochondrion B) ribosomeC) chloroplast D) nucleus

49. Process A occurs within the

A) CAT and GTA B) AAU and UUAC) GUG and UGU D) CAG and GUA

50. Process B involves the pairing of a codon with a triplet code on a transfer RNAmolecule. A correct pairing would be

Base your answers to questions 51 through 53 on the diagram below of a biochemicalprocess and on your knowledge of biology.

A) leucine B) glycine C) valine D) histidine

51. Which amino acid would be transferred to the position of codon CAC?

A) nucleus B) cytoplasm C) lysosome D) vacuole

52. The synthesis of structure X occurred in the

A) nucleolus B) ribosomeC) chloroplast D) mitochondrion

53. The biochemical process represented in the diagram is most closely associated withthe cell organelle is known as the

54. Base your answer to the following questionon the diagram below and on yourknowledge of biology. The diagramrepresents a step in protein synthesis.

A) A-T-C-G-G-A-TB) A-U-C-G-G-A-UC) T-A-G-C-C-T-AD) U-T-C-G-G-U-T

If a sequence of nitrogenous bases on DNAstrand I is T-A-G-C-C-T-A, thecorresponding sequence on the RNA will be

A) using natural selection to produce anew variety of cat

B) altering the reproductive rate of catsC) changing the behavior of catsD) manipulating the DNA of cats

55. For those individuals who have an allergicreaction to cats, a company in Los Angelespromises relief. They offer a new line of catsgenetically modified to eliminate or reducetheir allergy-causing properties. Thedevelopment of this new line of cats mostlikely involved

A) asexual reproduction in the wild for many yearsB) changes in light availabilityC) competition between plantsD) selective breeding over many generations

56. The arrows in the diagram below indicate the development of four different varietiesof vegetable plants from wild mustard.

Each of these varieties was most likely produced as a result of

A) environmental selectionB) alteration of DNA moleculesC) selective breedingD) a sudden mutation

57. The pedigree of Seattle Slew, a racehorseconsidered by some to be one of the fastesthorses that ever lived, includes very fasthorses on both his mother's side and hisfather's side. Seattle Slew most likely was aresult of

A) differentiationB) cloningC) gene insertionD) selective breeding

58. In order to produce the first white marigoldflower, growers began with the lightestyellow-flowered marigold plants. Aftercrossing them, these plants produced seeds,which were planted, and only the offspringwith very light-yellow flowers were used toproduce the next generation. Repeating thisprocess over many years, growers finallyproduced a marigold flower that isconsidered the first white variety of itsspecies. This procedure is known as

A) This technique results in offspring thatare genetically identical to the parents.

B) New varieties of organisms can bedeveloped by this technique known asselective breeding.

C) This technique is used by farmers toeliminate mutations in future membersof the species.

D) Since the development of cloning, thistechnique is no longer used inagriculture.

59. Which statement provides accurateinformation about the technique illustratedbelow?

Base your answers to questions 60 and 61 onthe statement below and on your knowledgeof biology.

Scientists have found a gene in theDNA of a certain plant that could be thekey to increasing the amount of lycopene,a cancer-fighting substance, in tomatoes.

A) recyclingB) mitosisC) enzyme actionD) gene expression

60. The ability to produce increased amounts oflycopene will be passed on to new tomatocells as a direct result of

A) selective breedingB) genetic engineeringC) cloningD) replication

61. The process of inserting this gene into theDNA of a tomato plant is known as

A) larger, and move slower B) larger, and move fasterC) smaller, and move faster D) smaller, and move slower

62. A student performed a gel electrophoresis experiment. The results are represented inthe diagram below.

Compared to the fragments at the top of the gel, the fragments at the lower end are

A) knowledge of sexual reproduction inplants

B) knowledge of the structure of starchmolecules

C) knowledge of the development ofembryos

D) knowledge of the structure of a DNAmolecule

63. A laboratory technique is represented in thediagram below.

Which knowledge was needed to developthis technique?

A) Enzymes are used to assemble an insulin gene, which is then attached to bacterialDNA.

B) Bacterial DNA is cut from a human DNA strand and inserted into a human cell toform an insulin gene.

C) The insulin gene is cut out of a human DNA strand using an enzyme and insertedinto bacterial DNA, resulting in a combination of different DNA segments.

D) A gene is deleted from bacterial DNA to produce an insulin gene, which is theninserted into human DNA.

64. Which statement would most likely be used to describe the procedure represented inthe diagram below?

A) selective breeding-growth hormoneB) cloning-antibioticsC) genetic engineering-insulinD) replicating-glucose

65. Which set of terms correctly identifies theprocedure shown in the diagram below anda substance produced by this procedure?

A) chromatographyB) gel electrophoresisC) direct harvestingD) genetic engineering

66. The diagram below represents a techniqueused in some molecular biology laboratories.

What is this technique an example of?

A) 1 B) 2 C) 3 D) 4

67. In some people, the lack of a particular enzyme causes a disease. Scientists areattempting to use bacteria to produce this enzyme for the treatment of people with thedisease. Which row in the chart below best describes the sequence of steps thescientist would most likely follow?

A) Bacterial cells will destroy defectivehuman genetic material.

B) Bacterial cells may form a multicellularembryo.

C) The inserted human DNA will changeharmful bacteria to harmless ones.

D) The inserted human DNA may directthe synthesis of human proteins.

68. The diagram below represents a geneticprocedure.

Which statement best describes the outcomeof this procedure?

69. Base your answer to the following question on the diagram below and on yourknowledge of biology.

A) natural selection B) asexual reproductionC) sexual reproduction D) gene deletion

Which process is indicated by letter B?

A) chromatographyB) direct harvestingC) meiosisD) genetic engineering

70. Which process is illustrated in the diagrambelow?

A) production of a human embryo to aidwomen who are unable to have children

B) change of single-celled organisms tomulticellular organisms

C) introduction of a toxic substance to killbacterial cells

D) production of hormones or enzymes toreplace missing human body chemicals

71. The diagram below represents a commonlaboratory technique in molecular genetics.

One common use of this technology is the

A) a specific carbohydrateB) a specific enzymeC) hormonesD) antibodies

72. A product of genetic engineering technologyis represented below.

Which substance was needed to join theinsulin gene to the bacterial DNA as shown?

A) The offspring contain half the original number of chromosomes in each method.B) The DNA in the offspring is genetically identical to that of the original organism

in both methods.C) The offspring produced by method A contain twice the original number of genes,

while those produced by method B contain half the original number of genes.D) The number of DNA bases is less than that of the original organism in method A

,but more than the original number in method B.

73. Two methods of reproduction are represented in the diagram below.

How does the DNA in the offspring produced by these methods compare to the DNAin the original organism?

A) the genes of the new animals aredifferent from those of the original pets

B) half of the genetic information of thenew animals is the same as that of theoriginal pets

C) the new animals have mutations notfound in the original pets

D) the new animals have the same geneticinformation as the original pets

74. Modern technology could be used to clonepet dogs and cats. The cloned animals wouldresemble the original pets because

A) Gametes from sheep A and sheep B were united to produce Dolly.B) The chromosome makeup of Dolly is identical to that of sheep A .C) Both Dolly and sheep C have identical DNA.D) Dolly contains genes from sheep B and sheep C .

75. The diagram below represents the process used in 1996 to clone the first mammal, asheep named Dolly.

Which statement concerning Dolly is correct?

A) The one leaf cell removed formed a zygote that developed into a new plant bymitotic cell division.

B) This procedure is used to produce new tomato plants that are clones of theoriginal tomato plant.

C) The cell taken from the leaf produced eight cells, each having one-half of thegenetic information of the original leaf cell.

D) The new tomato plant will not be able to reproduce sexually because it wasproduced by mitotic cell division.

76. A technique used to produce new plants is represented in the diagram below.

Which statement is best supported by the information in the diagram?

A) sheep A , onlyB) sheep B , onlyC) both sheep A and BD) both sheep A and C

77. Steps in a reproductive process used toproduce a sheep with certain traits are listedbelow.

Step 1 —The nucleus was removed from anunfertilized egg taken from sheep A .Step 2 —The nucleus of a body cell taken from sheepB was then inserted into this unfertilized eggfrom sheep A .Step 3 —The resulting cell was then implanted intothe uterus of sheep C .Step 4 — Sheep C gave birth to sheep D .

Which sheep would be most geneticallysimilar to sheep D?

A) cloningB) fertilizationC) biological adaptationD) DNA production

78. The nucleus is removed from a body cell ofone organism and is placed in an egg cellthat has had its nucleus removed. The resultof this is the production of organisms that isgenetically alike. What is this processknown as?

Base your answers to questions 79 through 82 on the information and diagram belowand on your knowledge of biology.

DNA samples were collected from four children. The diagram below representsthe results of a procedure that separated the DNA in each sample.

79. State one way information obtained from this procedure can be used.

80. The DNA is most similar in which two children? Support your answer.

A) largest fragment of DNA that traveled the fastestB) smallest fragment of DNA that traveled the fastestC) largest fragment of DNA that traveled the slowestD) smallest fragment of DNA that traveled the slowest

81. Band X represents the

82. Identify the procedure used to obtain these results.

Base your answers to questions 83 and 84 on the diagram below, which illustratessome steps in genetic engineering and on your knowledge of biology.

83. State one way that enzymes are used in step 2.

A) a new type of molecular base is formedB) different types of minerals are joined togetherC) DNA from the bacterial cell is clonedD) DNA from different organisms is joined together

84. What is the result of step 3?

Base your answers to questions 85 and 86 on the information below and on yourknowledge of biology.

The sequences below represent the same portions of a DNA molecule from thesame gene used by a student to study the relationship between two plant species. Abiological catalyst that recognizes the CCGG site is used to cut the DNA moleculesinto pieces. The catalyst cuts the DNA between the C and G of the site.

85. Are the two species of plants closely related? Support your answer.

86. Draw lines in the sequences below for species 1 and species 2 to show where thecatalyst would cut the DNA.

Base your answers to questions 87 and 88 on the Universal Genetic Code Chart belowand on your knowledge of biology.

87. Based on the information provided in the completed table, which plant species is mostclosely related to the endangered species? Support your answer.

Species:_______________________

88. Complete the missing mRNA base sequences for plant species B in the table above.

89. Base your answer to the following question on the chart below and on your knowledgeof biology.

Fill in the missing mRNA bases and the amino acid sequence that corresponds to theDNA base sequence below.

Base your answers to questions 90 and 91 on "the information and chart below and onyour knowledge of biology.

In DNA, a sequence of three bases is a code for the placement of acertain amino acid in a protein chain. The table below shows some aminoacids with their abbreviations and DNA codes.

"90. Describe how a protein would be changed if a base sequence mutates from GGA to

TGA.

91. Identify one environmental factor that could cause a base sequence in DNA to bechanged to a different base sequence.

92. Base your answer to the following question on the table below, which represents theDNA codes for several amino acids.

The original DNA sequence undergoes the following change:

TACACACAAACGGGG ®TACACACAAACGGGT

State one reason this mutation produces no change in the action of the final moleculethat will be synthesized from this code.

Base your answers to questions 93 and 94 on the information below and on yourknowledge of biology.

DNA samples were taken from three different species and used to determine theamino acid sequence for a portion of a particular protein. The amino acids were thencompared in order to determine which species were most closely related. Some ofthe information is shown on the table below.

93. Using the Universal Genetic Code Chart below, fill in the missing amino acidsequences in the table for species A and species B.

94. State one specific effect on the protein produced if an mRNA code is changed fromAGU to AGA.

95. Base your answer to the following question on the information below and on yourknowledge of biology.

Bacterial resistance to antibiotic treatment is becoming an increasing problemfor the medical community. It is estimated that 70% of bacteria that causeinfections in hospitals are resistant to at least one of the drugs used for treatment.Dangerous strains of tuberculosis (TB) have emerged that are resistant to severalmajor antibiotic drugs. While drug-resistant TB is generally treatable, it requiresmuch longer treatments with several antibiotics that are very expensive.

Explain the loss of effectiveness of antibiotic drugs. In your explanation, be sure to:

96. A child is born with a genetic disorder toparents who show no symptoms of thedisorder. Explain the type of information agenetic counselor might provide to theseparents. In your answer, be sure to: • explain why the child exhibitssymptoms of the genetic disorder eventhough the parents do not • identify one technique that can be usedto detect a genetic disorder • identify one genetic disorder

97. Scientists have successfully cloned sheep and cattle for several years. A farmer isconsidering the advantages and disadvantages of having a flock of sheep cloned froma single individual. Discuss the issues the farmer should take into account beforemaking a decision. Your response should include:

• how a cloned flock would be different from a noncloned flock• one advantage of having a cloned flock• one disadvantage of having a cloned flock• one reason that the farmer could not mate these cloned sheep with each other toincrease the size of his flock• one reason that the offspring resulting from breeding these sheep with an unrelatedsheep would not all be the same

98. Arrange the following structures fromlargest to smallest.a chromosomea nucleusa gene

99. For many years, humans have used a variety of techniques that have influenced thegenetic makeup of organisms. These techniques have led to the production of newvarieties of organisms that possess characteristics that are useful to humans. Identify one technique presently being used to alter the genetic makeup of an organism, andexplain how humans can benefit from this change. Your answer must include at least:

• the name of the technique used to alter the genetic makeup• a brief description of what is involved in this technique• one specific example of how this technique has been used• a statement of how humans have benefited from the production of this newvariety of organism

Answer KeyGenetics Regents Review

1. B2. C3. B4. B5. D6. C7. C8. A9. B10. B11. C12. A13. A14. B15. B16. B17. A18. A19. B20. C21. A22. D23. A24. B25. C26. C27. B28. A29. B30. B31. A32. B

33. D34. C35. D36. A37. C38. C39. C40. A41. C42. D43. A44. A45. A46. D47. D48. B49. D50. B51. D52. A53. B54. B55. D56. D57. C58. D59. B60. B61. B62. C63. D64. C

65. C66. D67. C68. D69. B70. D71. D72. B73. B74. D75. B76. B77. B78. A79. to determine

paternity/maternity— help solve acrime — identifyan accident victim— diagnosedisorders

80. B and D are themost similarbecause they havethe most bands incommon.

81. B82. electrophoresis —

gel electrophoresis— DNAfingerprinting

83. Examples: —Enzymes are usedto cut the DNA. —to cut the geneticmaterial

84. D

85. — No, thebiological catalystmade two cuts inspecies 1 DNA andonly one cut inspecies 2 DNA. —No, the catalyst cutthe DNA of species1 into three piecesand cut the DNA ofspecies 2 into onlytwo. — No, 15 outof 24 bases aredifferent. — No,the base sequencesare very different.

86.

87. – It is most closelyrelated to theendangered speciesbecause their aminoacid sequences areidentical. – It ismost closely relatedto the endangeredspecies because theDNA sequences arethe most similar.

88.

89.

Answer KeyGenetics Regents Review

90. Examples: Theshape of the proteinmay be changed. —The amino acidsequence would bedifferent. — Theprotein wouldcontain threonineinstead of proline.— The proteinbeing synthesizedmay not workcorrectly. — Theprotein will not beable to function.

91. Examples: ultraviolet light —radiation — X rays— chemicals

92. • GGG and GGTboth code forproline • The samemolecule will beproduced. • Thelast three bases stillcode for proline. •The same aminoacid sequence isproduced.

93.

94. – The amino acidARG will besubstituted forSER. – The shapeof the protein mightchange. – Theprotein might notwork.

95. • identifying thegenetic event thatresulted in theoriginal antibioticresistance in somestrains of bacteria.— mutation— achange in the DNAcode

• explaining howthe overuse ofantibiotics canincrease bacterialresistance.— Antibiotics killonly nonresistantstrains. Resistantbacteria surviveand reproduce.—Overuse ofantibiotics selectsfor resistant strainsof bacteria.

96. (essay)

97. (essay)

98. — nucleus,chromosome, gene

99. (essay)

Answer KeyGenetics Regents Review

96. • why the child exhibits symptoms of the genetic disorder even though the parents do not, such as: —Nondisjunction could have occurred. — A mutation might have taken place. — The child may haveinherited two recessive alleles.• identifying one technique that can be used to detect a genetic disorder, such as: — amniocentesis —karyotyping — blood screening — electrophoresis• identifying one genetic disorder, such as: — Down syndrome — sickle-cell anemia — hemophilia

97. • Acceptable responses include, but are not limited to:— There would be no variation.— All would be identical genetic copies, unlike noncloned herds, where much genetic diversity would bepresent. — All sheep would be the same.• Acceptable responses include, but are not limited to:— All sheep would have one or more desired traits (that the original individual possessed).• Acceptable responses include, but are not limited to:— Since all are the same, the entire flock could be lost if a disease to which they have no resistance wereto infect them.— The sheep may have a genetic flaw.— shorter life span• They would all be the same sex, so they could not mate with each other.• Acceptable responses include, but are not limited to:— Both parents contribute genes to the offspring.— Different gene combinations will result.

99. • The name of the technique used to alter the genetic makeup (e.g., genetic engineering, geneticmanipulation, selective breeding, gene therapy) [Note: Cloning is not acceptable because it representsduplication rather than alteration.] • a brief description of what is involved in this technique (e.g., a segment of DNA is moved from oneorganism to another organism) • one specific example of how this technique has been used (e.g., the gene for insulin production has beeninserted into certain bacteria) • a statement of how humans have benefited from the production of this new variety of organism (e.g.,more insulin is readily available from these bacteria than from extractions from pancreases of animals)