BIO352 Final Exam Review PDF

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Notes with Dr. Chandlee...

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Genetics Final Exam Review : Exam 1 1) In giant Amazonian water lilies, red alleles ( R ) and white alleles (W) are incompletely dominant, which means that heterozygotes are pink. If a pink lily is pollinated by a pink lily, what percentage of the offspring will bed red?" # a) 100%" # b) 0 %" c) 50%" d) 25%" # e) 75%" 2) A test cross used to determine if the genotype of a plant with the dominant phenotype is homozygous or heterozygous. If the unknown is heterozygous, half of the offspring of the test cross have the ________ phenotype. If the unknown is homozygous, all of the offspring will have the ________ phenotype." # a) dominant, incompletely dominant " # b) dominant, recessive" # c) dominant, epistatic " # d) recessive, dominant " # e) co-dominant, complimentary" 3) In lima beans, green color is dominant over yellow color. A cross between a pure breeding green bean and a pure breeding yellow bean yields 20 hybrid beans. A cross between two of these hybrid beans yielded 180 F2 beans. How many of these F2 beans should be green?" # a) none" # b) 90" # c) 45" # d) 180" # e) 135" 4) How many different gametes can be formed from the genotype AaBbCCDdEe?" # a) 4" # b) 6" # c) 16" # d) 2" # e) 32" 5) The chemical ________ is used to keep replicated chromosomes from separating during anaphase leading to a doubling of the amount of genetic material in the cells:" # a) acetone" # b) formaldehyde " # c) colchicine " # d) alcohol" # e) ribonucleic acid" 6) Triplods:" # a) can be produced by the fusion of a diploid and a haploid gamete" # b) are usually sterile" # c) all of the listed answers except one" # d) result in downs syndrome" # e) have difficulty in meiosis because the non-paired chromosomes have no homologue "

7) Which of the following individuals will have the MOST trouble in producing functional gametes during meiosis?" # a) cannot tell with the information given" # b) tetraploid with 12 total chromosomes" # c) tetraploid with 48 total chromosomes" # d) triploid with 30 total chromosomes" # e) diploid with 46 total chromosomes" 8) An autotetraploid plant is of the genotype Aaaa. If this plant is self-fertilized what proportion of the progeny will be aaaa?" # a) 1/4" # b) 2/9" # c) 1/9" # d) 1/36" # e) 36/784" 9) If an affected male has affected daughters and sons in about the same number as unaffected daughters and sons, the trait is most likely to be an:" # a) autosomal dominant trait" # b) autosomal recessive trait" # c) x-linked dominant trait" # d) x-linked recessive trait" # e) none of the above" 10) A coefficient of coincidence is:" # a) measure of genetic diversity in a population " # b) measure of the number of human chromosomes segregating during meiosis" # c) measure relating to the interference of one crossover with another" # d) none of the listed answers" # e) measure of the probability of linkage between two loci " 11) The number of Barr bodies in a human somatic cell is:" # a) one in every male and none in every female" # b) the same as the number of x chromosomes in the cell" # c) one more than the number of x chromosomes in the cell" # d) the same as the number of functionally active x chromosomes in the cell" # e) one less than the number of x chromosomes in the cell" 12) Two percentage of recombination equals a distance between the loci of: " # a) 200 map units# # # d) 20 map units" # b) 0.002 map units# # # e) 2 map units " # c) 0.2 map units" 13) A heterozygous trihybrid corn plant is test crossed and the following progeny are produced (all traits are recessive to their wild type alternative):" booster, booster, silkless, liguleless, liguleless, silkless, wildtype, silkless, booster, liguleless, silkless, booster, liguleless, " What is the order of the loci on the chromosome?" # a) cannot tell with the information given" # b) booster, silkless, liguleless " # c) silkless, liguleless, booster" # d) liguleless, booster, silkless" # e) liguleless, silkless, booster"

14) Why does using only two genes for estimating gene distance underestimate the actual distance between the two genes?# " # a) chiasma form too infrequently" # b) only two chromatids are involved in the event at any one time" # c) double crossing over goes undetected" # d) the coincidence is too small to arrive at the correct distance" # e) interference tends to allow over-estimation of the distance " 15) Which of the following does not belong with the other four?" # a) translocation" # b) deletion" # c) inversion" # d) duplication" # e) polyploidy " 16) "

If we have a chromosome with three loci in which the distance between the loci is as indicated, then the probability of a double crossover is:" # a) cannot tell with the information given" # b) 0.180" # c) 0.081" # d) 0.016" # e) 0.900" 17) Which of the following is not true about crossing over?#" # a) more than one listed" # b) it occurs before DNA synthesis" # c) it involves a physical exchange of genetic material between non-sister chromatids" # d) it occurs during prophase II of meiosis" # e) none of the above " 18) Genetic recombination as a result of crossing over occurs more readily in genes:" # a) that are located on different chromosomes " # b) that are located far apart on the same chromosome" # c) that are located close together on the same chromosome " # d) that are on the sex chromosomes" # e) that are on the autosomes" 19) When an organism gains or loses one or more chromosomes but not a complete haploid set, the condition is known as:" # a) trisomy" # b) aneuploidy" # c) polyploidy" # d) triploidy" # e) euploidy " 20) Two practical benefits of polyploidy that have been exploited by breeders are:" # a) sterility and enhanced flavor in fruits " # b) none of the answers listed" # c) the associated bigger cell size and sterility" # d) the associated bigger cell size and enhanced reproductive capacity"

21) What phenotype ratio would you expect from the test cross of an F1 individual that gives a 12:3:1 in the F2?" # a) 1:1:1:1" # b) 3:1" # c) 15:1" # d) 1:2:1" # e) none of the above " # " 22) Given incomplete dominance among the pairs of alleles at two of four loci and complete dominance/recessiveness among the pairs of alleles at the other two loci, a cross between two tetra hybrids will produce how many different phenotypes (assume independent assortment) among the offspring? " # a) 81" # b) 36" # c) 18" # d) 49" # e) 27" 23) If shape and color of gourds are determined by 2 genes, each with dominant/recessive alleles, crossing two dihybrid heterozygotes will produce ___________ different phenotypes among the progeny.# " # a) 9" # b) 3" # c) 2" # d) 4" # e) 5" 24) 640 F2 progeny from a standard dihybrid cross are scored. How many do you expect to have the same phenotype as the F1 parents (assume complete dominance at both loci and independent assortment)." # a) 40" # b) 120" # c) 160" # d) 320" # e) 360" 25) Which of the following has the potential to cause non-Mendelian phenotypic segregation ratios:" # a) epistasis " # b) lethal alleles" # c) alleles exhibiting incomplete or partial dominance " # d) all of the above" # e) none of the above" # f) two of the above " 26) The presence of ovaries in a human female is an example of:" # a) dominance " # b) a sex-limited trait" # c) penetrance " # d) expressivity" # e) a sex-influenced trait"

27) For an organism with 1N=10, how many pairs of homologous chromosomes are present at metaphase II of the second meiotic division:" # a) 20" # b) 35" # c) 15" # d) 10" # e) 0" 28) Which of the following is a test cross?" # a) aabb x AaBb" # b) none of the answers listed" # c) AaBb x AaBb" # d) AABB x AABB" # e) AaBb x AABB" 29) At what stage of meiosis do sister chromatids separate?# " # a) anaphase II" # b) prophase I" # c) sister chromatids do not separate, except by crossing over" # d) prophase II" # e) anaphase I" 30) Polydactyly is a single gene, dominant trait that causes extra fingers and toes. The number of extra digits varies from individual to individual with polydactyly. This demonstrates the concept of:" # a) expressivity" # b) co-dominance " # c) a sex-limited trait" # d) incomplete dominance " # e) penetrance " 31) In a dihybrid cross, SsYy x SsYy, what fraction of the offspring will be homozygous for both traits?# " # a) 1/16" # b) 3/4# " # c) 1/8# " # d) 1/4" # e) 3/16" 32) Two unlinked loci effect mouse hair color. CC or Cc mice have colored hair. Mice with genotype cc are albino because all pigment production and deposition of pigment in hair is blocked. At the second locus, the B allele (black coat) is dominant to the b allele (brown coat). A mouse with a black coat is mated with an albino mouse of genotype bbcc. Half of the offspring are albino, one quarter are black, and one quarter are brown. What is the genotype of the black parent?" # a) BBcc" # b) BbCc" # c) bbCC" # d) BBCC" # e) BbCC"

33) In radishes, red and white are the pure-breeding colors and long and round are the purebreeding shapes. The hybrids are purple and oval. The cross of a white, oval and a purple, oval will produce more:" # a) red, long than white, long" # b) purple, round than white, oval" # c) purple, round than white, long" # d) purple, oval than purple, long" # e) purple, oval than purple, long" 34) If a complementation test is performed by crossing two independently derived but similar looking wingless strains of Drosophilia melanogaster, and all the resulting progeny still have no wings, you would conclude that:" # a) the original wingless strains carry mutant alleles in different genes, both of which contribute to wing formation" # b) the original wingless strains carry mutant alleles in the same gene that determines wing formation" # c) no definitive conclusions can be drawn" # d) crossing over had occurred " # e) the genes are inherited in a non-Mendelian fashion " 35) A couple has 4 children whose blood types are A, A, B, and AB. Which of the following parental genotypes are capable of producing the blood types of this couples children:" # a) IAIO and IBIO" # b) IBIO and IOIO" # c) IAIO and IOIO" # d) more than one of the above " # e) IAIO and IBIB" # " 36) What phenotypic ratio would you expect from the test cross of an F1 individual that gives a 9:7 in the F2?" # a) 1:1:1:1" # b) 3:1" # c) 15:1" # d) 1:2:1" # e) none of the above" 37) How many different gametes can be formed from the genotype AaBBCCDDEe?" # a) 2^3" # b) 4^2" # c) 2^4" # d) 3^2" # e) 2^2" 38) If an ant has a diploid number of 24 chromosomes, how many chromatids are in a cell during prophase of mitosis?" # a) 60" # b) 24" # c) 48" # d) 36" # e) 12"

39) Mendel’s unit factors of heredity are most accurately known to be:" # a) one maternal and one parental chromatid" # b) identical alleles on homologous chromosomes" # c) two maternal chromatids# " # d) two alleles for a gene on a maternal and paternal homologue of a homologous pair" # e) two alleles on non-homologous chromosomes " 40) The alleles at two different genes always assort independently:" # a) when the female is carrying a recessive trait" # b) if both genes are dominant" # c) if the genes are on different pairs of homologous chromosome" # d) if the genes are on the same pair of homologous chromosome" # e) if they exhibit epistasis " 41) A diploid cell with 8 chromosomes in all undergoes meiosis. Assuming no crossing over, what is the chance that any one gamete will contain only the maternally-contributed chromosomes of the diploid cell?# " # a) 1/10" # b) 1/128" # c) 1/32" # d) 1/16" # e) 1/64" 42) In an F1 x F1 dihybrid cross, a 9:3:3:1 phenotypic ratio would be expected unless:" # a) the two genes show epistatic interactions" # b) the two genes compliment each other" # c) the two genes are independently assorting " # d) there is complete dominance at both loci" # e) none of the above" 43) A linear chromosome with the centromere at the very end of the chromosome is called:" # a) sub-metacentric" # b) telocentric" # c) metacentric" # d) acrocentric " # e) none of the above " 44) Given two individuals who are both heterozygous at 4 loci (assume dominant/recessive alleles at both loci), how many different phenotypes are possible among their progeny?" # a) 32" # b) 2" # c) 8" # d) 12" # e) 16" 45) Starting with a P generation with the following genotypes (AABB x aabb) and assuming classical Mendelian inheritance, what is the expected phenotypic ratio observed among the F2 progeny?" # a) 9:3:3:1" # b) 1:1" # c) 1:1:1:1" # d) 1:2:1" # e) 3:1"

46) If you were examining a skin (somatic) cell during one complete cycle, which of the following would you never observe?" # a) synapsis" # b) metaphase" # c) prophase" # d) interphase" # e) anaphase " 47) In meiosis, separation of the homologous chromosomes occurs during:" # a) Telophase II" # b) Metaphase II" # c) Anaphase I" # d) Anaphase II" # e) Metaphase I" 48) A child has blood type A. The mother has blood type AB. Which of the following genotypes would exclude a male from being the father?" # a) AO" # b) OO" # c) AB" # d) none of these are excluded" # e) BO" 49) Mendel’s laws and where each occurs in Meiosis are as follows:" # a) none of the answers listed" # b) the principle of segregation states that two members of a gene pair segregate from each other in the formation of gametes (demonstrated in Metaphase II). The principle of independent assortment states that the alleles for genes for different traits assort independently of each other (demonstrated in Anaphase II). " # c) the principle of segregation states that two members of a gene pair segregate from each other in the formation of gametes (demonstrated in Anaphase I). The principle of independent assortment states that the alleles for genes for different traits assort independently of each other (demonstrated in Metaphase I)." # d) the principle of segregation states that two members of a gene pair segregate from each other in the formation of gametes (demonstrated in Metaphase I). The principle of independent assortment states that the alleles for genes for different traits assort independently of each other (demonstrated in Anaphase II)."

ANSWER KEY" 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12. 13. 14. 15. 16. 17. 18. 19. 20. 21. 22. 23. 24. 25. 26. 27. 28. 29. 30. 31. 32. 33. 34. 35. 36. 37. 38. 39. 40. 41. 42. 43. 44. 45. 46. 47. 48. 49.

D" D" E" C" C" C" D" A" A" C" E" E" D" C" E" D" A" B" B" C" D" B" D" E" D" B" E" A" A" A" D" B" D" B" A" B" E" C" D" C" D" A" B" E" A" A" C" D" B"

Name _________________________________________" Exam 1 Practice Test" 1) _______" 2) _______" 3) _______" 4) _______" 5) _______" 6) _______" 7) _______" 8) _______" 9) _______" 10) _______" 11) _______" 12) _______" 13) _______" 14) _______" 15) _______" 16) _______" 17) _______" 18) _______" 19) _______" 20) _______" 21) _______" 22) _______" 23) _______" 24) _______" 25) _______" 26) _______" 27) _______" 28) _______" 29) _______" 30) _______" 31) _______" 32) _______" 33) _______" 34) _______" 35) _______" 36) _______" 37) _______" 38) _______" 39) _______" 40) _______" 41) _______" 42) _______" 43) _______" 44) _______" 45) _______" 46) _______" 47) _______" 48) _______" 49) _______" Total Correct ______ out of 49"

Genetics Final Exam Review : Exam 2 1) Suppose you discover a new variant in which hamsters have long tails instead of the usual stubby tails. You notice that this trait seems only to be present in males. To investigate this pattern, you cross a long-tail male with a true-breeding-stubby-tail female, and find that all of the F1 progeny of both sexes have stubby tails. You then interbreed the F1 and observe that all of the F2 females have stubby tails, but 1/2 of the F2 males have long tails. You conclude that:" # a) the stubby allele is y-linked" # b) the stubby allele is an x-linked recessive" # c) the stubby allele is an autosomal dominant " # d) the stubby allele is autosomal recessive " # e) the stubby allele is an x-linked dominant " 2) What is the easiest way to determine if a particular trait of an organism is autosomally inherited or is sex-linked?# " # a) perform selfing crosses" # b) simply look at the individuals" # c) perform reciprocal cross" # d) perform a test cross" # e) any of the above " 3) In the WZ/ZZ system, males are the heterogametic sex." # a) False" # b) True" 4) You observe the progeny of a Drosophilia cross to consist of all red-eyed females and whiteeyed males. What do you infer the parental phenotypes to be?" # a) b or c" # b) red-eyed females and red-eyed males" # c) white-eyed females and white-eyed males" # d) red eyed females and white-eyed males" # e) white eyed females and red-eyed males" 5) Why do mapping experiments become less accurate when the distances between genes become larger?" # a) none of the answers listed" # b) crossover gametes become less common" # c) recombination occurs less frequently in long chromosomes" # d) multiple crossovers are more common" # e) interference is greater when the distance between genes is large" 6) Assume that, regarding a particular gene, one scored 40 second division ascospore arrangements (2:2:2:2 or 2:4:2) and 60 first division arrangements (4:4) in Neurospora. What would be the map distance between the gene and the centromere?# " # a) 10" # b) 20" # c) 40" # d) insufficient information provided to answer this question " # e) 60"

7) One Drosophilia genotype PpMm is crossed with another genotype ppmm. If the genes are absolutely linked in cis in the dihybrid parent:" # a) 10% of the progeny will be phenotypically PM and 90% phenotypically pm" # b) all of the progeny will be phenotypically PM" # c) 50% of the progeny will be phenotypically PM and 50% phenotypically pm" # d) all of the progeny will be phenotypically pm" # e) none of the above" " 8) If we have a chromosome with three loci in which the distance between the loci is as indicated, then the probability of a double cross over is:" # a) 0.0081" # b) 0.900" # c) 0.180" # d) 0.016" # e) none of the above " 9) With nondisjunction, which parent leads to the sex chromosomes aneuploid XYY?" # a) either parent" # b) both parents" # c) mother" # d) father" # e) none of the above; nondisjunction only occurs during animal clothing " 10) A husband and wife have normal vision, although both of their fathers are red-green color blind, which is inherited an an x-linked recessive condition. What is the probability that their first child will be normal vision and male?" # a) 0" # b) 1" # c) 0.5" # d) 0.25" # e) none of the above " 11) Genetic recombination as a result of crossing over occurs more readily in genes:" # a) that are located on different chromosomes" # b) that are on the same sex chromosomes" # c) that are located close together on the same chromosomes" # d) that are on the autosomes" # e) that are located far apart on the same chromosome" 12) In test cross experiments, the frequency of recombination between genes a and d is 0.3; between d and c, 0.2; and b, 0.1; between a and c, 0.5; and between b and d, 0.3. What is the order of the three genes?" # a) a-b-c-d" # b) c-b-d-a" # c) a-d-c-b" # d) d-c-a-b" # e) b-a-c-d " "

13) A plant of genotype Cd/Cd is crossed to cD/cD and an F1 test crossed to cd/cd. If the genes are linked and 40 map units apart, the percentage of Cd/cd offspring will be:" # a) 50%" # b) 40%" # c) 30%" # d) 20%" # e) 10%" # " 14) The Drosophilia genes for white eyes (w), tan body (t) and vestigial wings (vg) lie at map positions 2,12, and 42 respectively. The distance, therefore, between w and t is 10, t and vg is 30 and w and vg is 40. Out of 1000 progeny, 21 exhibited double crossovers. What is the degree of interference? (Hint: I=1-C.C)" # a) 0.10" # b) 0.20" # c) 0.40" # d) 0.30" # e) none of the above " 15) Tortoise-shell cats have a patchwork coloration pattern of orange and black spots. This pattern is an example of:" # a) maternal inheritance " # b) somatic mutation" # c) mitotic segregation" # d) cytoplasmic inheritance " # e) x-inactivation " 16) How does the y chromosome determine maleness in humans?" # a) by containing a gene coding for the TDF, a protein that directs the development of female gonads" # b) by containing the genes for steroid metabolism" # c) by containing the autosomal genes responsible for the SRY effects" # d) by containing the structural genes for testes p...