Name # Class Date Regents Review: Genetics/DNA 1. Gregor Mendel formulated some basic principles of heredity from the results of his experiments with A) Drosophila B) bacteria C) four-o'clock plants D) pea plants 2. Information about patterns of human heredity is more difficult to obtain than information about patterns of heredity in fruit flies because A) humans have shorter life cycles and more offspring than fruit flies B) most humans have offspring with hidden dominant traits C) humans have longer life cycles and fewer offspring than fruit flies D) most mating in humans is carefully controlled by genetic engineering 3. Which structures code information for the inheritance of traits? A) nuclear membranes B) cell membranes C) vacuoles D) genes 4. For a given trait, the two genes of an allelic pair are not alike. An individual possessing this gene combination is said to be A) homozygous for that trait B) heterozygous for that trait C) recessive for that trait D) pure for that trait 5. Two pea plants, hybrid for a single trait, produce 60 pea plants. Approximately how many of the pea plants are expected to exhibit the recessive trait? A) 15 B) 45 C) 30 D) 60 6. A cross between two tall garden pea plants produced 314 tall plants and 98 short plants. The genotypes of the tall parent plants were most likely A) TT and tt B) TT and Tt C) Tt and Tt D) TT and TT 7. In a certain species of plant, the allele for tallness is dominant over the allele for shortness. To determine whether a tall plant is heterozygous or homozygous, it should be crossed with a A) short plant B) tall plant C) medium-sized plant D) different species of plant 8. When round squash are crossed with long squash, all offspring are oval in shape. How many different genotypes are expected when round squash are crossed with oval squash? A) 1 B) 2 C) 3 D) 4 9. Which example illustrates the modification of a phenotype by an environmental factor? A) A homozygous gray squirrel is the same color as a heterozygous gray squirrel. B) Pink-flowering four-o'clocks that were allowed to self-pollinate produced offspring with red, pink, and white flowers. C) Seedlings germinated in darkness are white, but most of these seedlings turn green when placed in light. D) A person heterozygous for sickle-cell anemia has a higher-than-normal resistance to malaria. 10. Goldfish kept in a small, crowded aquarium grew to a relatively small size. When these same goldfish were released into a large natural body of water, many of them greatly increased in size. One possible explanation for this observation is that the size of these goldfish is dependent on the A) genotype, only B) environment, only C) interaction between the environment and heredity D) number of gene mutations occurring in the small tank 11. The cells that make up the skin of an individual have some functions different from the cells that make up the liver because A) all cells have a common ancestor B) different cells have different genetic material C) environment and past history have no influence on cell function D) different parts of genetic instructions are used in different types of cells 12. Which statements best describe the relationship between the terms chromosomes, genes, and nuclei? A) Chromosomes are found on genes. Genes are found in nuclei. B) Chromosomes are found in nuclei. Nuclei are found in genes. C) Genes are found on chromosomes. Chromosomes are found in nuclei. D) Genes are found in nuclei. Nuclei are found in chromosomes. 13. Which statement best describes the process of crossing-over? A) It takes place between homologous chromosomes and results in new gene combinations. B) It takes place between nonhomologous chromosomes and results in an increased gene mutation rate. C) It takes place between homologous chromosomes and results in an increased gene mutation rate. D) It takes place between nonhomologous chromosomes and results in new gene combinations.
14. Which illustration of a chromosomal change best represents a chromosome mutation known as a deletion? A) B) C) D) 15. Mutagenic agents are substances that A) increase the rate of gene mutations B) decrease the rate of gene mutations C) have no effect upon the rate of gene mutations D) cause gene mutations but not other chromosomal changes 16. Amniocentesis is a process that is used to A) determine the rate of mutation in embryos B) examine the phenotypes of fruit flies C) detect many genetic disorders in humans before birth D) search for polyploid fruit seeds 17. The diagram below represents a photographic enlargement of replicated chromosomes from a fetal cell. For which technique would this photograph be used to determine if the chromosomes of the fetus exhibit any genetic abnormalities? A) cleavage B) plasmolysis C) chemosynthesis D) karyotyping 18. Tay-Sachs is a genetic disorder characterized by a deterioration of the A) circulatory system B) nervous system C) excretory system D) endocrine system 19. Which is a genetic disorder in which abnormal hemoglobin leads to fragile red blood cells and obstructed blood vessels? A) phenylketonuria B) sickle-cell anemia C) leukemia D) Down's syndrome 20. Base your answer to the following question on your knowledge of biology and on the charts below which show human chromosomes arranged in pairs. Which genetic disorder in individual A is indicated by the number of chromosomes labeled 21? A) phenylketonuria (PKU) B) Tay-Sacks C) sickle-cell anemia D) Down's syndrome 21. Which blood type would not appear in the offspring of parents who had genotypes I A I B and I A i? A) A B) B C) AB D) O 22. Which statement correctly describes the normal number and type of chromosomes present in human body cells of a particular sex? A) Males have 22 pairs of autosomes and 1 pair of sex chromosomes known as XX. B) Females have 23 pairs of autosomes. C) Males have 22 pairs of autosomes and 1 pair of sex chromosomes known as XY. D) Males have 23 pairs of autosomes. 23. Which diagram represents a sperm that can unite with a normal egg to produce a zygote that will develop into a normal human male embryo? A) B) C) D) 24. If a defective gene occurs on the X-chromosome, it will normally be transmitted to male offspring only by A) the mother B) the father C) segregation D) mutation
25. Base your answer to the following question on the diagram below and on your knowledge of biology. Base your answers to questions 29 and 30 on the diagram below, which represents some components involved in cellular protein synthesis, and on your knowledge of Biology. Strand A would normally be found in the A) plasma membrane B) ribosome C) vacuole D) nucleus 26. Which scientists developed the molecular model represented below? 29. How many codons are located on the messenger RNA molecule in the diagram? A) 1 B) 6 C) 3 D) 9 30. Molecules C, D, and E will combine to form part of A) a polypeptide B) a polysaccharide C) DNA D) RNA 31. When humans first domesticated dogs, there was relatively little diversity in the species. Today, there are many variations such as the German shepherd and the dalmatian. This increase in diversity is most closely associated with A) Mendel and Darwin B) Watson and Crick C) Lamarck and Weismann D) Miller and Fox 27. The coded information of a DNA molecule is determined by the A) sequence of amino acids B) number of ribose units C) sequence of the nitrogenous bases D) sequence of the sugar-phosphate units 28. What is the complementary messenger-rna sequence for the DNA sequence shown below? A) cloning of selected body cells B) selective breeding C) mitotic cell division D) environmental influences on inherited traits 32. Which process is a common practice that has been used by farmers for hundreds of years to develop new plant and animal varieties? A) cloning B) genetic engineering C) cutting DNA and removing segments D) selective breeding for desirable traits A) C-A-A-G-G-U B) G-T-T-C-C-A C) G-U-U-C-C-A D) C-A-A-G-G-T
33. The diagram below represents a technique currently used by scientists in the field of biotechnology. Which statement describes a possible outcome of this technique? A) The bacterium is able to produce a human hormone. B) It allows the bacterium to grow in humans, since it contains a human gene. C) It allows humans to become immune to an infection from this type of bacteria. D) The bacterium can now produce human cells identical to cells of the DNA donor. 34. Steps in a reproductive process used to produce a sheep with certain traits are listed below. Step 1 The nucleus was removed from an unfertilized egg taken from sheep A. Step 2 The nucleus of a body cell taken from sheep B was then inserted into this unfertilized egg from sheep A. Step 3 The resulting cell was then implanted into the uterus of sheep C. Step 4 Sheep C gave birth to sheep D. Which sheep would be most genetically similar to sheep D? A) sheep A, only B) sheep B, only C) both sheep A and B D) both sheep A and C 35. The diagram below represents four beakers, each containing an equal number of two colors of beads. One bead was removed at random from each of the four beakers, and the colors were recorded. The beads were then returned to the original beakers. When the procedure was repeated several times, different combinations of colored beads were obtained. This activity could best be used to illustrate A) mitotic cell division B) sex linkage C) crossing-over D) independent assortment 36. When red-flowered snapdragons are crossed with white-flowered snapdragons, all the F1 plants will have pink flowers. If Mendel had used snapdragons instead of pea plants, he would have had difficulty in formulating his principle of A) dominance B) sex-linked traits C) multiple alleles D) mutation
37. The diagram below shows a diploid cell with two homologous pairs of chromosomes. Due to independent assortment what possible normal allelic combinations could be found in gametes produced from this cell by meiosis? A) Aa, Bb, AA, and bb B) AaBb and ABab C) AB and Ab, only D) AB, Ab, ab, and ab 38. The genetic concepts of segregation and recombination are best illustrated when A) corn seeds are exposed to mutagenic agents B) plants that are heterozygous for a trait are crossed C) plant genotypes are influenced by environmental factors D) geraniums are produced by vegetative propagation 39. The diagram below represents the inheritance of stem height in garden peas. 42. When a brown mink and a silver-blue mink were crossed, all of the offspring produced were brown. When these offspring were mated, they produced 60 brown minks and 20 silver-blue minks. Of the 60 brown minks, the number that are heterozygous should be closest to A) 10 B) 20 C) 40 D) 60 43. In humans, the ability to roll the tongue is dominant over the inability to roll the tongue. If two parents who are homozygous dominant for this trait have 8 children, how many children would be expected to be unable to roll their tongues? A) 0 B) 2 C) 8 D) 4 44. B represents the dominant allele for a trait and b represents the recessive allele. In which pair of crosses must all of the offspring produced have the same phenotype? A) Bb bb and Bb Bb B) Bb bb and BB Bb C) BB Bb and BB bb D) BB BB and Bb Bb 45. In pea plants, the gene for yellow seeds is dominant over the gene for green seeds. Which procedure can be used to determine if a plant that produces yellow seeds is homozygous or heterozygous? A) crossing it with plants that are homozygous for yellow seeds B) crossing it with plants that are homozygous for green seeds C) crossing it with plants that are known to contain mutant genes D) exposing it to high doses of radiation 46. In rabbits, the gene for black coat color (B) is dominant over the gene for white coat color (b). In the cross illustrated below, rabbit member III may have genotype BB or Bb. The diagram best illustrates A) intermediate inheritance B) segregation and recombination C) sex linkage and codominance D) independent assortment 40. In poultry, feathered shank (F) is dominant over clean shank (f). If the hen's genotype is represented by ff and the rooster's genotype is Ff, what percentage of their offspring would be expected to have feathered shanks? A) 0% B) 50% C) 75% D) 100% 41. In rats, black coat color is dominant over white coat color. If some of the offspring of a cross between a black rat and a white rat are white, the black rat must have been A) a polyploid B) homozygous C) heterozygous D) a mutation Which cross should be done to help determine if rabbit number III is heterozygous? A) Cross I with II a second time. B) Cross III with a rabbit having genotype BB. C) Cross III with a rabbit having genotype bb. D) Cross III with II. 47. A gardener found that when white petunias and purple petunias were crossed, only blue petunias were produced. From which of the following crosses would the gardener most probably obtain the greatest percentage of white petunias? A) white and blue petunias B) purple and purple petunias C) blue and blue petunias D) purple and blue petunias
48. If two roan cattle are crossed, what percent of the offspring are expected to show the parental phenotype for coat color? A) 25% B) 50% C) 75% D) 100% 49. Crosses between white-coated cattle (C W C W ) and red-coated cattle (C R C R ) produce roan offspring (C R C W ). This type of inheritance pattern is known as A) multiple allele inheritance B) crossing-over C) sex linkage D) codominance 50. A certain species of plant produces blue flowers when the soil ph is above 7.0. However, when the soil ph is below 7.0, the flowers are pink. Which statement best explains this color change? A) Mutagenic agents can alter genotypes. B) The environment influences gene action. C) Polyploidy produces 2n gametes. D) Chromosomal mutations produce color effects. 51. Identical twins were born with genes for a genetic disorder that can be controlled by diet. Both twins were placed on this diet, which excludes a certain amino acid. However, one twin chose not to follow the diet and developed the genetic disorder. The other twin followed the diet and did not develop the disorder. This difference between the twins illustrates that A) gene expression is not influenced by biochemical factors B) identical twins do not always have the same genotype C) gene expression is influenced by the environment D) the genetic disorder is inherited by identical twins, only 52. During the warm temperatures of summer, the arctic fox produces enzymes that cause its fur to become reddish brown. During the cold temperatures of winter, these enzymes do not function. As a result, the fox has a white coat that blends into the snowy background. This change in fur color shows that A) the genes of a fox are made of unstable DNA B) mutations can be caused by temperature extremes C) random alteration of DNA can occur on certain chromosomes D) the expression of certain genes is affected by temperature 53. The diagrams below show two pairs of homologous chromosomes present in the diploid cells of a fruit fly. The locations of the alleles for eye color and wing shape are indicated. According to this information, eye color is A) dominant over wing shape B) linked to wing shape C) recessive to wing shape D) independent of wing shape 54. Genes for two different traits that are located next to each other on the same chromosome would most likely be A) inherited separately B) codominant C) recombined D) inherited together 55. The results of a genetic process are represented in the diagram below. Which process most likely produced these results? A) chromosomal mutation during mitosis B) nondisjunction during meiosis C) independent assortment during mitosis D) crossing-over during meiosis 56. Which change involves the loss of part of a chromosome? A) deletion B) addition C) base substitution D) gene mutation 57. In certain plants, each cell contains double the normal chromosome number. These 4n cells are an example of the condition known as A) replication B) diploidy C) polyploidy D) disjunction 58. Overexposure of animals to x-rays is dangerous because x-rays are known to damage DNA. A direct result of this damage is cells with A) unusually thick cell walls B) no organelles in the cytoplasm C) abnormally large chloroplasts D) changes in chromosome number or structure
59. X-rays, formaldehyde, and asbestos fibers are all similar in that they are A) animal preservatives B) used to treat diseases C) used to diagnose diseases D) mutagenic agents 60. Which mutation could be passed on to future generations? A) a gene change in a liver cell B) cancer caused by excessive exposure of skin cells to the Sun C) a chromosomal alteration during gametogenesis D) random breakage of a chromatid in a leaf cell of a maple tree 61. A woman has a gene that causes a visual disorder. To prevent the disorder from appearing in future generations, the defective gene would have to be repaired in the mother's A) nervous system B) reproductive cells C) eye D) uterus 62. A woman who is homozygous for type A blood marries a man who is homozygous for type B blood. All of their children have type AB blood. This type of inheritance is known as codominance because A) some of the children would be expected to have type O blood B) the allele for type A blood is dominant, and the allele for type B blood is recessive C) the allele for type B blood is dominant, and the allele for type A blood is recessive D) the allele for type A blood and the allele for type B blood are both expressed in the children 63. Based on the pattern of inheritance known as sex linkage, if a male is a hemophiliac, how many genes for this trait are present on the sex chromosomes in each of his diploid cells? A) 1 B) 2 C) 3 D) 0 64. When a colorblind woman marries a male with normal vision, all their daughters have normal vision and all their sons are colorblind. This is an example of which type of inheritance? A) multiple alleles B) codominance C) sex linkage D) autosomal dominance 65. Part of a molecule found in cells is represented below. Which process is most directly affected by the arrangement of components 1 through 4? A) diffusion through cell membranes B) fertilization of a sex cell C) sequencing of amino acids in cells D) increasing the number of cells in an organism 66. The diagram below represents a portion DNA molecule. The letters represent different types of A) sugar molecules B) molecular bases C) enzymes D) proteins 67. Four different segments of a DNA molecule are represented below. There is an error in the DNA molecule in A) segment 1, only B) segment 3, only C) segments 2 and 3 D) segments 2 and 4 68. In a DNA sample, 15% of the bases are thymine (T).What percentage of the bases in this sample are adenine (A)? A) 15% B) 30% C) 35% D) 85%
69. Which pair of molecules, when bonded together, would most likely be found in a nucleotide of DNA? A) ribose and adenine B) ribose and thymine C) deoxyribose and guanine D) deoxyribose and uracil Base your answers to questions 70 through 72 on the diagram below of a DNA molecule and on your knowledge of biology. 70. The base sequence of strand X is A) C-A-T-G B) A-C-G-T C) A-C-T-G D) G-C-T-A 71. Which activity occurs in the process of replication? 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. 72. Structure 3 represents a A) phosphate B) deoxyribose sugar C) ribose sugar D) base 75. Which situation would most likely produce a gene mutation in a squirrel? A) The squirrel stops using its claws for digging. B) The squirrel is exposed to radiation for several days. C) Oak trees gradually become less common. D) The weather becomes wetter for a short period of time. 76. If a portion of a messenger RNA molecule contains the base sequence A-A-U, the corresponding transfer RNA base sequence is A) A-A-U B) G-G-T C) T-T-C D) U-U-A 77. Which base is normally used in the synthesis of RNA but not in the synthesis of DNA? A) adenine B) uracil C) cytosine D) guanine 78. A sequence of three nitrogenous bases in a messenger-rna molecule is known as a A) codon B) gene C) polypeptide D) nucleotide 79. What is the sequence of subunits in a protein most directly dependent on? A) the region in the cell where enzymes are produced B) DNA in the chromosomes in a cell C) the type of cell in which starch is found D) kinds of materials in the cell membrane 80. Which statement best describes the relationship between cells, DNA, and proteins? A) Cells contain DNA that controls the production of proteins. B) DNA is composed of proteins that carry coded information for how cells function. C) Proteins are used to produce cells that link amino acids together into DNA. D) Cells are linked together by proteins to make different kinds of DNA molecules. 73. Which event takes place first during DNA replication? A) A single-stranded RNA molecule is formed. B) Transfer RNA links to an amino acid. C) Free nucleotides are bonded together in the correct sequence. D) The DNA molecule "unzips" along weak hydrogen bonds. 74. A change in the base subunit sequence during DNA replication can result in A) variation within an organism B) rapid evolution of an organism C) synthesis of antigens to protect the cell D) recombination of genes within the cell
81. The diagram below represents a portion of an organic molecule. This molecule controls cellular activity by directing the synthesis of A) carbohydrates B) minerals C) fats D) proteins 82. Some farmers currently grow genetically engineered crops. What would be an argument against the use of this technology? A) it increases crop production B) it produces insect-resistant plants C) its long-term effects on humans are still being investigated D) it always results in crops that do not taste good 83. In order to produce the first white marigold flower, growers began with the lightest yellow-flowered marigold plants. After crossing them, these plants produced seeds, which were planted, and only the offspring with very light-yellow flowers were used to produce the next generation. Repeating this process over many years, growers finally produced a marigold flower that is considered the first white variety of its species. This procedure is known as A) differentiation B) cloning C) gene insertion D) selective breeding
84. A technique used to alter cells is represented in the diagram below. The genetic material contained in the nucleus of each of the new cells is most likely A) identical to that in the original body cell B) identical to that in the original egg cell C) 50% the same as the original egg cell and 50% the same as the original body cell D) 25% the same as the original egg cell and 7.5% the same as the original body cell 85. Goats have been genetically modified to produce an anticlotting protein in their milk The protein is extracted from the milk and given to people who have inherited a disorder that causes their bodies to produce blood clots, which can be fatal. A benefit of the technology used to produce this protein is that it A) can be used to overcome the effects of a harmful mutation B) can provide people with a new kind of nutrient-rich milk C) will result in healthier goats with more nutritious milk for their offspring D) will reduce blood clots in other farm animals that are modified in this way 86. Which process produces only identical offspring? A) meiotic cell division B) selective breeding C) cloning D) fertilization 87. Scientists have successfully cloned animals, including large mammals such as sheep. Which statement provides the most likely reason that a human has not yet been cloned? A) Humans have DNA that is structurally very different from other mammals. B) Cloning can only he performed on animals that normally reproduce asexually. C) Human genes are made of too many different types of simple sugars. D) Some people consider human genetic experiments unethical. 88. In 1996, scientists cloned the first mammal, a sheep. This technique involved the removal of the nucleus from an egg cell. The nucleus from a cell of another adult sheep was then inserted into this egg cell. Once this cell began to develop into an embryo, it was implanted into a third female sheep that later gave birth to a healthy lamb, Dolly. Which statement concerning Dolly is correct? A) Her offspring would be genetically identical. B) Dolly and her DNA donor are genetically identical. C) Two different gametes were manipulated to produce Dolly. D) Dolly was produced by the recombination of genetic material.
Base your answers to questions 89 and 90 on the passage below. The number in the parenthesis ( ) at the end of a sentence is used to identify that sentence. They Sure Do Look Like Dinosaurs When making movies about dinosaurs, film producers often use ordinary lizards and enlarge their images thousands of times (1). We all know, however, that while they look like dinosaurs and are related to dinosaurs, lizards are not actually dinosaurs (2). Recently, some scientists have developed a hypothesis that challenges this view (3). These scientists believe that some dinosaurs were actually the same species as some modern lizards that had grown to unbelievable sizes (4). They think that such growth might be due to a special type of DNA called repetitive DNA, often referred to as junk DNA because scientists do not understand its functions (5). These scientists studied pumpkins that can reach sizes of nearly 1,000 pounds and found them to contain large amounts of repetitive DNA (6). Other pumpkins that grow to only a few ounces in weight have very little of this kind of DNA (7). In addition, cells that reproduce uncontrollably have almost always been found to contain large amounts of this type of DNA (8). 89. Write the number of a sentence that provides evidence that supports the hypothesis that increasing amounts of repetitive DNA are responsible for increased sizes of organisms. 90. Which kind of cells would most likely contain large amounts of repetitive DNA? A) red blood cells B) cancer cells C) nerve cells D) cells that are unable to reproduce Base your answers to questions 91 through 94 on the information and diagram below and on your knowledge of biology. DNA samples were collected from four children. The diagram below represents the results of a procedure that separated the DNA in each sample. 91. State one way information obtained from this procedure can be used. 92. The DNA is most similar in which two children? Support your answer.
93. Band X represents the A) largest fragment of DNA that traveled the fastest B) smallest fragment of DNA that traveled the fastest C) largest fragment of DNA that traveled the slowest D) smallest fragment of DNA that traveled the slowest 94. Identify the procedure used to obtain these results.
Base your answers to questions 95 through 97 on Universal Genetic Code Chart below and on your knowledge of biology.
95. Based on the information provided in the completed table, which plant species is most closely related to the endangered species? Support your answer. Species: 96. Complete the missing mrna base sequences for plant species B in the table above. 97. Complete the missing amino acid sequences for plant species A in the table above.
Base your answers to questions 98 through 100 on the information below and on your knowledge of biology. The sequences below represent the same portions of a DNA molecule from the same gene used by a student to study the relationship between two plant species. A biological catalyst that recognizes the CCGG site is used to cut the DNA molecules into pieces. The catalyst cuts the DNA between the C and G of the site. 98. Complete the data table below to show the results of the action of the catalyst. 99. Draw lines in the sequences below for species 1 and species 2 to show where the catalyst would cut the DNA. 100. Are the two species of plants closely related? Support your answer.
Answer Key Genetics & DNA Regents Review 1. D 40. B 79. B 96. 2. C 41. C 80. A 3. D 42. C 81. D 4. B 43. A 82. C 5. A 44. C 83. D 6. C 45. B 84. A 7. A 46. C 85. A 8. B 47. A 86. C 97. 9. C 48. B 87. D 10. C 49. D 88. B 11. D 12. C 13. A 14. A 15. A 16. C 17. D 18. B 19. B 20. D 21. D 22. C 23. B 24. A 25. D 26. B 27. C 28. C 29. C 30. A 31. B 32. D 33. A 34. B 35. D 36. A 37. D 50. B 51. C 52. D 53. D 54. D 55. D 56. A 57. C 58. D 59. D 60. C 61. B 62. D 63. A 64. C 65. C 66. B 67. B 68. A 69. C 70. C 71. B 72. A 73. D 74. A 75. B 76. D 89. Sentence 6 or 7 provides evidence that supports the hypothesis. 90. B 91. to determine paternity/maternity or help solve a crime or identify an accident victim or diagnose disorders 92. B and D are the most similar because they have the most bands in common. 93. B 94. electrophoresis or gel electrophoresis or DNA fingerprinting 95. It is most closely related to the endangered species because their amino acid sequences are identical. It is most closely related to the endangered species because the DNA sequences are the most similar. 98. 99. 100. No, the biological catalyst made two cuts in species 1 DNA and only one cut in species 2 DNA. No, the catalyst cut the DNA of species 1 into three pieces and cut the DNA of species 2 into only two. No, 15 out of 24 bases are different. No, the base sequences are very different. 38. B 77. B 39. B 78. A