Genetics Review Questions 2014 KEY

BIO 30 GENETICS January Diploma Exam Questions JANUARY 1996 Use the following information to answer the next two questions. Which row correctly identifies one genetic factor and one environmental factor that might cause the described changes in the sex ratio? Row Genetic Factor Environmental Factor A. X-linked disorders affect more males than females. A male pre-embryo has a greater chance of successful implantation than a female preembryo. B. X-linked disorders affect more females than males. A male pre-embryo has a greater chance of successful implantation than a female preembryo. C. X-linked disorders affect more males than females. Accidents are the leading cause of death among males aged 15 to 35 years. D. X-linked disorders affect more females than males. Accidents are the leading cause of death among males aged 15 to 35 years. Which statement provides the best explanation for the underlying cause of the sex ratio at conception? Sperm that contain an X chromosome are more motile than those that contain a Y chromosome. Sperm that contain a Y chromosome are more motile than those that contain an X chromosome. There is a greater probability that males will produce sperm that contain an X chromosome than those that contain a Y chromosome. There is a greater probability that males will produce sperm that contain a Y chromosome than those that contain an X chromosome. Use the following information to answer the next two questions. A folded-eared female mated with a male of unknown phenotype. All six of their offspring had pointed ears. What were the most probable genotypes of the parents? pp and PP Pp and Pp pp and Pp pp and pp Numerical Response 07. A curly-haired, five-digited male was crossed with a female that was heterozygous for both hair type and the number of digits on the paws. What is the probability of this mating producing offspring that have curly hair and are heterozygous for the number of digits on the paws? (Record your answer as a value from 0 to 1, rounded to two significant digits, in the numerical response section of the answer sheet.) Answer: __0.25_____ Use the following information to answer the next two questions. What was the genotype of the male parent in this cross? eb+eb+ vg+vg+ eb+eb vg+vg+ eb+eb vg+vg eb+eb vgvg How many of the 44 offspring with grey bodies and long wings would be expected to be heterozygous for body colour? 44 33 22 11 Use the following information to answer the next two questions. Which statement is consistent with the information given? Thal-1 and Thal-2 are codominant and N is dominant. Thal-1 is dominant over both N and Thal-2. N is dominant over both Thal-1 and Thal-2. N, Thal-1, and Thal-2 are codominant. If a male with the genotype N Thal-1 and a female with the genotype N Thal-2 have a child, the probability of that child having some degree of anemia (either mild or moderate) is 1.00 0.75 0.50 0.25 Use the following information to answer the next TWO questions. The ability to smell some odours and not others is an inherited trait. This trait is an example of incomplete dominance crossing over a phenotype a genotype If a gene responsible for the production of an odour-receptor protein underwent a mutation, one result might be a decrease in the ability to smell a specific odour an increase in the ability to smell a variety of other odours a decrease in protein synthesis within all olfactory neurons an increase in threshold levels of stimulation for receptor neurons Numerical Response 08. Czar Nicholas II was not a hemophiliac. His wife, Alexandra, was a carrier for hemophilia. What was the probability that any of their daughters was a carrier for hemophilia? (Record your answer as a value from 0 to 1, rounded to two significant digits, in the numericalresponse section of the answer sheet.) Answer: __0.50_____ January 1997 Use the following information to answer the next question. In the F1 generation, the allele for yellow seeds would have been found in about 50% of the female gametes and 50% of the male gametes produced by F1 plants all of the female gametes and none of the male gametes produced by F1 plants all of the male gametes and none of the female gametes produced by F1 plants none of the male gametes or female gametes produced by F1 plants Use the following information to answer the next three questions. The phenotypic ratio of a cross between YyTt pea plant and a yyTt pea plant is 3 yellow tall : 3 yellow short : 1 green tall : 1 green short 1 yellow tall : 1 yellow short : 1 green tall : 1 green short 3 yellow tall : 1 yellow short : 3 green tall : 1 green short 1 yellow tall : 1 yellow short : 3 green tall : 3 green short In a cross between an RrYy plant and an RRYY plant, what fraction of the offspring would be expected to have the genotype RRYy? 1/2 1/4 3/8 1/8 Numerical Response 05. What percentage of the gametes produced by a pea plant heterozygous for both seed shape and seed colour would be expected to contain both the allele for wrinkled and the allele for green? (Record your answer as a whole number in the numerical-response section of the answer sheet.) Answer: ____25_______% Use the following information to answer the next question. Which pattern of inheritance for flower colour is demonstrated by this sweet pea plant variant? X-linked recessive Autosomal recessive Autosomal dominant Incomplete dominance Use the following information to answer the next question. Numerical Response 06. A man who is heterozygous for the disease allele marries a woman who is homozygous for the normal recessive allele. What is the probability that their first child is a boy and has Huntington’s disease? (Record your answer as a value from 0 to 1, rounded to two decimal places, in the numerical response section of the answer sheet.) Answer: _____0.25______ Use the following information to answer the next two questions. Of the following, the parent and child combination that could be possible is parents 1 and baby Y parents 2 and baby Z parents 3 and baby W parents 4 and baby X Numerical Response 01. The probability that a mother with blood type O and a father with the genotype IBi would have a child with blood type O is __________. (Record your answer as a value from 0 to 1, rounded to two decimal places, in the numericalresponse section of the answer sheet.) Answer: ___0.50________ Use the following information to answer the next two questions. A colour-blind male with brown eyes and his green-eyed wife who has normal colour vision have a daughter who is colour-blind and has blue eyes. What is the genotype of this child? XcbXcbBb XcbXcbGb XcbXcbbb XcbYbb Use the following additional information to answer the next question. If individual 1 has blue eyes, genotypes of her parents could be mother XXbb, father XcbYGB mother XXcbGb, father XYBb mother XXcbGG, father XYbb mother XXcbGb, father XcbYBB Numerical Response 01. Three genes have been identified on chromosome two in Drosophila (fruit flies). They control eye colour, body hair (bristles), and wing shape. The genes are: 1 cinnabar eyes 2 short bristles 3 curved wings The crossover frequency between 1 and 3 is 18%, between 2 and 3 is 24.5 %, and between 1 and 2 is 6.5%. Construct a gene map of three genes and indicate their order by number. (Record your three-digit answer in the numerical-response section of the answer sheet.) Answer: _____213 OR 312______ Use the following information to answer the next question. This information indicates that the genotype for the unknown male is likely homozygous heterozygous either homozygous recessive or heterozygous either homozygous dominant or heterozygous JANUARY 1998 Use the following information to answer the next three questions. If the traits for seed coat texture and seed coat colour had been located close together on the same chromosome, Mendel might not have conceptualized gene pairs dominance the Law of Segregation the Law of Independent Assortment Numerical Response 01. The F2 seed phenotype ratio that Mendel obtained upon crossing two heterozygous smooth and yellow F1 individuals would have been __________. (Record your four-digit answer in the numerical-response section of the answer sheet.) Answer: ____3______ : ____1______ : ___9______ : ____3______ smooth and wrinkled and smooth and wrinkled and green green yellow yellow Use the following additional information to answer the next question. This type of cross is referred to as a test cross monohybrid cross homozygous cross heterozygous cross Use the following information to answer the next two questions. What is the probability of obtaining a black puppy from the following cross? BbEe x BbEE 9/16 3/16 3/4 ¼ Numerical Response 02. Two dogs, each with the genotype BbEe, were crossed. What is the percentage probability that their offspring would have yellow coat colour? (Record your answer as a whole number percentage in the numerical-response section of the answer sheet.) Answer: __25____ Use the following information to answer the next question. What ratio of wild-type to white-eyed progeny can be expected in each sex if F1 females are crossed to males of the same genotype as their father? Males – 1:0, females – 1:0 Males – 1:1, females – 1:0 Males – 0:1, females – 1:1 Males – 1:1, females – 1:1 __________________________ Use the following information to answer the next question. The crossover frequency between genes e and r is 3.5% 2.0% 1.5% 0.5% Use the following information to answer the next two questions. During meiosis, which pair of genes have the best chance of being transferred together to a new cell? Black body and purple eyes Purple eyes and speck body Dumpy wings and purple eyes Dumpy wings and speck body To determine whether this is an X chromosome or an autosome, a researcher would have to determine whether these traits are recessive dominant passed from male parents to their male offspring passed from female parents to their male offspring Use the following information to answer the next two questions. Which individual is a known homozygote for blood type? I_1 I_2 II_2 II_3 Which of the following rows correctly identifies the genotypes of individuals III-2 and III-3? Row Individual III-2 Individual III-3 A. IBi or IBIB IAi B. IBi IAi or IAIA C. IBi or IBIB IAi or IAIA D. IBi IAi JANUARY 1999 Use the following information to answer the next two questions. A valid assumption based on this information is that all types of colourblindness are sex-influenced males may be carriers for all types of colourblindness only females may be carriers for blue colourblindness blue colourblindness occurs in males and females with equal frequency Use the following additional information to answer the next question. Based on this pedigree, the probability that individual II-4 is a carrier is 50% it is impossible to determine whether individual II-6 is a carrier if individual III-5 is a carrier, all of her female children will have red–green colourblindness if individual II-3 is a carrier, there is a 50% chance that her male child will have red–green colourblindness Use the following information to answer the next question. Which of the following gene maps shows the correct sequence of these genes on chromosome 7? A Use the following information to answer the next three questions. Which term best describes the allele for cystic fibrosis? X-linked Recessive Dominant Codominant Use the additional information to answer the next two questions. The genotypes of the mother and father are both homozygous both heterozygous homozygous and heterozygous, respectively heterozygous and homozygous, respectively Numerical Response 03. These parents, who are unaffected by cystic fibrosis, are planning to have another child. What is the percentage probability that their next child will be affected by cystic fibrosis? (Record your answer as a whole number percentage in the numerical-response section on the answer sheet.) Answer: ____25______% Use the following information to answer the next question. A female with hypophosphatemia whose father had the disease but whose mother did not will likely transmit the disorder to her sons only her sons and her daughters equally all of her daughters but none of her sons all of her daughters and 50% of her sons Certain disorders result if an extra chromosome is present in all nucleated cells of the body (trisomy) or if a chromosome is missing from all nucleated cells of the body (monosomy). These disorders arise because of nondisjunction, a malfunction that occurs during DNA replication RNA transcription telophase of mitosis anaphase of meiosis Use the following information to answer the next question. What is the strand of DNA that would code for this portion of insulin? AAG CAA TTA GTT GTA AAA CAA TTC CAC CTA CAC GAG AAC GTA TTC TTC GTA AAC GAG CAC Use the following information to answer the next two questions. Numerical Response 04. A man, heterozygous for Marfan syndrome, and a homozygous recessive woman have a child. What is the probability that the child will be affected by Marfan syndrome? (Record your answer as a value from 0 to 1, rounded to two decimal places, in the numerical-response section on the answer sheet.) Answer: ____0.50______ Which of the following statements is a valid prediction about the frequency of this disorder in males and females? Males are affected more often than females. Females are affected more often than males. Males and females are affected with equal frequency. An accurate prediction cannot be made because the syndrome occurs randomly. Use the following information to answer the next two questions. Which two types of offspring are pure breeders for both plant height and seed shape? 1 and 6 2 and 5 3 and 8 4 and 7 Which two types of offspring, when crossed, could be expected to produce a population in which 50% of their offspring would be tall and 100% would produce round seeds? 1 and 8 2 and 4 3 and 7 5 and 6 Use the following information to answer the next question. The genotype of individual I-1 is ii IAi IBi IAIA Use the following information to answer the next question. Numerical Response 05. If a woman with the genotype IAIB Rr and a man with the blood type O Rh– have a child, what is the probability that the child will have blood type A Rh–? (Record your answer as a value from 0 to 1, rounded to two decimal places, in the numericalresponse section on the answer sheet.) Answer: ____0.25______ Use the following information to answer the next two questions. The genotypes of the parent plant with long V-shaped lines and of the parent plant with short V-shaped lines are, respectively, VhV1 and vv Vhv and V1v VhV1 and V1v Vhv and V1V1 Numerical Response 06. What is the probability of these two parent plants producing offspring that have unlined leaves? (Record your answer as a number between 0 and 1, rounded to two decimal places, in the numerical-response section on the answer sheet.) Answer: ____0.25______ JANUARY 2000 Use the following information to answer the next four questions. These data indicate that, regardless of its branch source, pollen has no effect on the leaf colour of resulting offspring. A reasonable explanation for this observation is that leaf colour is a codominant trait leaf colour is a dominant–recessive trait cell organelles or cytoplasm are active only in pollen cell organelles or cytoplasm contain genetic information Use the following additional information to answer the next question. With respect to the alleles for flower colour, these results indicate X-linked inheritance gene-linked inheritance dominant-recessive inheritance incomplete dominance inheritance Use the following additional information to answer the next two questions. The likely genotypes of the P1 plants for these two crosses is represented in row Row P1 genotypes scarlet-red-flowered offspring P1 genotypes orange-flowered offspring A. RPR ´ rr RR ´ rr B. RPRP ´ rr RR ´ rr C. RPr ´ RPr Rr ´ Rr D. RPRP ´ RR RPR ´ Rr Which of the following phenotypes is the predicted flower colour of M. jalapa with the genotype RPR? Yellow Orange Crimson Scarlet-red Use the following information to answer the next two questions. . Which of the following parental genotypes could produce offspring with the four different colour patterns? BBYy ´ BbYy BbYY ´ Bbyy bbYY ´ bbyy Bbyy ´ bbYy What is the probability of obtaining a blue parakeet when two green heterozygous parakeets are crossed? 0 3/16 1/4 9/16 Use the following information to answer the next question. Numerical Response 04. If 42% of the population have diabetes, then the percentage of the population who are carriers is calculated to be _____46_____%. (Record your answer as a whole number in the numerical-response section on the answer sheet.) Use the following information to answer the next two questions. If two heterozygous mice were mated, what percentage of their offspring would be predicted to die? 0% 25% 50% 75% JANUARY 2001 Use the following information to answer the next four questions. What type of inheritance is demonstrated in Tay-Sachs disease? Autosomal recessive Autosomal dominant Sex-linked recessive Sex-linked dominant If tuberculosis regained its former role as one of the world’s deadliest diseases, then the frequency of the Tay-Sachs allele over time would decrease because of a decreased selective advantage increase because of an increased selective advantage decrease because of an increased selective advantage remain the same as a result of Hardy–Weinberg equilibrium Numerical Response 04. A young couple decided to have genetic screening done to determine if they were carriers of Tay-Sachs disease. If both individuals were carriers, what percentage of their offspring would be predicted to have protection from tuberculosis but not have Tay-Sachs disease? Answer: ___50_______% (Record your answer as a whole number percentage in the numerical-response section on the answer sheet.) Use the following additional information to answer the next question. Genetic screening results show that an individual is a carrier of Tay-Sachs if the individual’s DNA binds to none of the DNA probes two of the normal allele DNA probes two of the defective allele DNA probes one of the normal allele DNA probes and one of the defective allele DNA probes Use the following information to answer the next two questions. The genetic composition of the parents is PpTt and PPTT PPTt and PpTT PpTt and PpTt PpTt and Pptt One of the green-stemmed, red-tomato plants was crossed with another tomato plant. One of the offspring was a purple-stemmed, yellow-tomato plant. If this offspring were crossed with a green-stemmed, yellow-tomato plant, then the possible phenotype or phenotypes of the offspring would be green-stemmed, yellow-tomato plants green-stemmed, yellow-tomato plants and purple-stemmed, yellow-tomato plants green-stemmed, yellow-tomato plants; purple-stemmed, yellow-tomato plants; and purple-stemmed, red-tomato plants green-stemmed, yellow-tomato plants; purple-stemmed, yellow-tomato plants; purple-stemmed, red-tomato plants; and green-stemmed, red-tomato plants Use the following information to answer the next two questions. During meiosis, which of the following pairs of genes has the greatest chance of being separated by crossing over? (m) and (d) (ne) and (p) (m) and (lc) (p) and (o) Use the following additional information to answer the next question. The cross-over frequency between genes O and S is 6% 29% 31% 97% Use the following information to answer the next three questions. In the dihybrid cross between the two black mice, the C allele codes for black colour brown colour colour absent colour present Numerical Response 06. What is the expected phenotypic ratio that results from a cross between two black mice heterozygous for both genes? Phenotypic Ratio: ____9_____ : ____3_____ : ___4______ Coat Colour: Black Brown White (Record your three-digit answer in the numerical-response section on the answer sheet.) Numerical Response 07. What is the expected phenotypic ratio resulting from a cross between a bbCc female mouse and BbCc male mouse? Phenotypic Ratio: ____3______ : ____3______ : ____2______ OR 664 Coat Colour: Black Brown White (Record your three-digit answer in the numerical-response section on the answer sheet.) _______________________________________ Use the following information to answer the next question. If the ram is heterozygous for white wool, the expected phenotypes of the offspring of the farmer’s test cross would be all black all white ½ black and ½ white ¾ black and ¼ white Use the following information to answer the next three questions. The normal function of the p53 gene is likely to encourage a cell to undergo mitosis encourage a cell to undergo meiosis prevent an abnormal cell from reproducing prevent the transcription of a cell suicide gene Use the following additional information to answer the next two questions. The initial research findings described above demonstrate that the activated p53 gene causes cancer in lab animals demonstrate that the p53 protein causes the formation of cancer cells indicate that the normal p53 gene is responsible for preventing cancer in all mammals indicate that the normal p53 gene is responsible for preventing cancer under laboratory conditions Gene therapy that might stop uncontrolled cell division due to the mutant p53 allele would require one functional p53 allele to be successfully inserted into cancer cells two functional p53 alleles to be successfully inserted into cancer cells one functional p53 allele to be successfully removed from cancer cells two functional p53 alleles to be successfully removed from cancer cells JANUARY 2002 Use the following information to answer the next three questions. Numerical Response 05. Using the numbers above, match these descriptions and symbols with the term below to which they apply. Description or Symbol Number: _____1____ _____3____ ___4______ ____2_____ Term: gene allele phenotype genotype (Record all four digits of your answer in the numerical-response section on the answer sheet.) What are the genotypes for coat colour of two horses that are predicted to produce offspring in a 1:1 genotypic ratio? Tt and tt Tt and Tt Tobiano and tobiano Tobiano and not tobiano Numerical Response 06. Given that the diploid number for horses is 64, what is the number of chromosomes found in a horse’s somatic cell and what is the number of chromosomes found in a horse’s gamete cell? Number of Chromosomes: __6__ __4__ , _3___ __2__ Cell Type: somatic cell gamete cell (Record all four digits of your answer in the numerical-response section on the answer sheet.) Use the following information to answer the next six questions. According to the data above, the relationship among these alleles is such that the black allele is codominant with the chocolate and cinnamon alleles black allele is codominant with the chocolate allele, and the chocolate allele is codominant with the cinnamon allele black allele is dominant over the chocolate and cinnamon alleles, and the chocolate allele is dominant over the cinnamon allele black allele is dominant over the chocolate and cinnamon alleles, and the chocolate and cinnamon alleles are codominant Use the following additional information to answer the next two questions. A blue-coloured female cat is bred with a cinnamon-coloured male cat. The offspring produced are black-coloured, blue-coloured, chocolate-coloured, and lilac-coloured. The genotypes of the parental cats are indicated in row Row Female Cat Male Cat A. Bbldd blblDd B. Bbldd blblDD C. Bbdd blblDd D. Bbdd blblDD A black-coloured female cat with the genotype BbDd is bred with a fawn-coloured male cat. The percentage of their offspring predicted to be chocolate-coloured is 13% 19% 25% 50% Use the following additional information to answer the next three questions. The phenotype of a female cat with genotype XrXrBbl would be a black cat an orange cat an orange-and-black cat an orange, black, and cinnamon cat A cinnamon-coloured male cat (XrYblbl) is bred with an orange-coloured female cat (XRXRBB). What possible phenotypes could be produced in the offspring? Tortoiseshell-coloured female cats and orange-coloured male cats Tortoiseshell-coloured female cats, black-coloured female cats, and black-coloured male cats Cinnamon-coloured male cats, orange-coloured female cats, and tortoiseshell-coloured female cats Cinnamon-coloured male cats, black-coloured male cats, black-coloured female cats, orange-coloured female cats, and tortoiseshell-coloured female cats Use the following additional information to answer the next question. What is the predicted phenotype of a female cat with genotype XRXRBbldd? Black Orange Cinnamon Cream (light orange) Use the following information to answer the next six questions. The probability of two carrier parents having a child with sickle cell anemia is 25% 50% 75% 100% If scientists are successful in significantly reducing or eliminating malaria, the best prediction for what will happen to the allele for sickle cell anemia in the population is that it will not be affected by the elimination of malaria increase as its selective advantage is increased be reduced as its selective advantage is decreased quickly disappear as its selective advantage is increased