TEST BANK FOR GENETICS FROM GENES TO GENOMES 6TH EDITION BY HARTWELL | COMPLETE ALL CHAPTERS

A particular flower can be purple, blue, red, or white. A pure-breeding purple plant is crossed with a pure-breeding white plant and the F1 are then crossed to produce an F2 generation. Which phenotypic ratio in the F2 may indicate that flower color in these plants is controlled by two genes that interact additively? - 9:3:3:1 In primroses, the dominant allele of gene K is necessary to synthesize blue flower pigment. Blue pigment synthesis is inhibited by a dominant allele of gene D. In other words, plants with the genotype K- D- will not produce pigment (and their flowers will be white) because of the presence of the D allele. 26) If two dihybrid plants (Kk Dd) are crossed, what is the ratio of blue to white offspring in the progeny? - 3 blue: 13 white 27) What type of gene interaction determines flower color in primroses? - two genes with dominant epistasis Two pure-breeding phlox plants were crossed, one with dark-blue flowers and the other with pink flowers. The F1 generation all had dark-blue flowers. When the F1 were crossed with each other, the F2 generation consisted of 176 plants: 101 with dark-blue flowers, 33 with light-blue flowers, 30 with red flowers, and 10 with pink flowers. 28) How is flower color controlled in phlox? - two genes whose alleles interact additively 29) What progeny types would result from crossing a homozygous plant with light-blue flowers to a homozygous plant with red flowers? - all would be dark blue Brooker Chapter 3 Chromosome Transmission During Cell Division and Sexual Reproduction 1) Check all that apply. In prokaryotic cells - genetic information is contained within a nucleoid region, genetic material is organized as a single circular chromosome and a cell wall surrounds the plasma membrane. 2) Organelles are - membrane-bound compartments of eukaryotic cells. 3) A karyotype is a(n) - organized representation of the chromosomes within a cell. 4) You are performing a karyotype for the first time and you forget to add the colchicine. How do you predict this will affect your karyotype? - The chromosomes in some cells will look normal (highly compacted) but in other cells distinct chromosomes will be hard to identify. 5) During sexual reproduction, each parent contributes one set of chromosomes. Members of a pair of chromosomes (one from each parent) are called . - homologs 6) Which of the following would contain genetic material that is 100% identical? - Sister chromatids 7) You are studying a diploid organism that has 14 pairs of chromosomes. How many chromatids would this cell have in G2 phase? - 56 8) You are studying a diploid organism that has 14 pairs of chromosomes. How many chromatids will a gamete from this organism have? - 14 9) You are studying a diploid organism that has 14 pairs of chromosomes. How manychromatids will a cell from this organism have in metaphase of meiosis II? - 28 10) The location of a gene on a chromosome is called its . - locus 11) Cell division in prokaryotic cells is called , while in eukaryotic cells it is called . - binary fission; mitosis 12) During this phase of the cell cycle, the sister chromatids are formed. - S phase 13) During this phase of the cell cycle chromosomes start to condense. - Prophase 14) During this phase of the cell cycle sister chromatids separate and head towards opposite poles of the cell. - Anaphase 15) During this phase of the cell cycle the chromosomes line up in the center of the cell. - Metaphase 16) During this phase of the cell cycle the nuclear membrane starts to disassociate. - Prophase 17) During this phase of the cell cycle the nuclear membrane reforms around the chromosomes. - Telophase 18) During this phase of the cell cycle the microtubules of the spindle fiber attach to the kinetochore. - Prometaphase 19) During this phase of the cell cycle the separated sister chromatids are considered independent chromosomes. - Anaphase 20) Which of the following indicates the correct order of these events? - Prophase - Prometaphase - Metaphase - Anaphase - Telophase 21) In animals, somatic cells are and germ cells are . - diploid; haploid 22) If the gametes of an organism are different morphologically, they are said to be . - heterogamous 23) The general purpose of the synaptonemal complex is to - provide a link between homologous chromosomes in meiosis. 24) What occurs during leptotene of prophase I? - The replicated chromosomes condense. 25) A bivalent contains how many chromatids? - 4 26) The process of crossing over occurs during which phase of meiosis? - Pachytene 27) What represents the correct order of events during prophase I? - Leptotene - zygotene - pachytene - diplotene - diakinesis 28) The physical structure that is formed when two chromatids cross over is called a(n) . - chiasma 29) If an organism has five pairs of chromosomes, how many chromosomal combinations are possible at metaphase I of meiosis? - 25 30) The end result of meiosis in animals is . - four haploid cells 31) Oogenesis is a gametogenic process involving that produces . - meiosis; egg cells 32) In plants, the haploid generation is called the and the diploid generation is called the . - gametophyte; sporophyte 33) In plants, spores are produced by the process of . - meiosis 34) A pollen grain in a plant represents the . - male gametophyte 35) In a plant, which of the following is triploid (3n)? - Endosperm 36) Which microtubule type is paired to its correct function? - Aster microtubules - positioning of the spindle apparatus 37) The chromosomal theory of inheritance was first proposed by . - Boveri and Sutton 38) In a species of turtles you are studying, you find that when eggs are incubated at a low temperature, the hatched turtle will be male. Eggs incubated at a high temperature yield females, and intermediate temperatures lead to both male and female offspring. This mode of sex determination is most similar to that in - alligators. 39) A male produced from an unfertilized haploid egg is an example of what type of sex determination system? - Haplo-diploid 40) In several mammals, including some rat and shrew species, the presence of two X chromosomes means the animal will be a female, whereas having just one X chromosome dictates maleness. This type of sex determination is most similar to - insects. 41) If an allele is inherited on the X chromosome, but not the Y, it is said to be an example of . - X-linked inheritance 42) Based on what you know about the biochemical composition of cells, the primary information containing building blocks of chromosomes are likely - nucleotides. 43) You are studying a type of cell that you don't know much about. You want to determine what organism the cell comes from. You decide to watch cell division in this plant using the appropriate cell biology tools. After some experimentation, you determine that cytokinesis inthis cell is sensitive to myosin inhibitors. You are likely studying - an animal cell. 44) The process where two gametes fuse with each other in the process of fertilization to begin the life of a new organism is called - sexual reproduction. 45) You are studying a new species of plant similar to Mendel's pea plants. You are specifically interested in two genes that are located on two different chromosomes. In this plant, the gene for height has two alleles, T (tall) and t (short). The gene for leaf color has two alleles P (purple) and p (pink). What meiotic products do you expect from diploid cells that are homozyous for the tall allele and heterozygous for the purple allele? - An equal number of TP and Tp gametes 46) You are performing a fruit fly cross similar to those that Morgan performed. Unfortunately, you forgot to write down the parents of your cross. You count the progeny, and find you have 40 red-eyed males, 80 red-eyed females, and 40 white-eyed males. Assuming that all genotypes from this cross should have equal survival rates, what are the genotypes of the parent flies? - Xw+Y and Xw+Xw 47) Zip1 is a protein in yeast that is required for synaptonemal complex formation. Assuming synaptonemal complexes are required for meiosis in yeast, where do you predict that cells lacking Zip1 will arrest (stop progressing through meiosis)? - Between the zygotene and pachytene stages 48) Vincristine is a cancer chemotherapy drug. It binds to tubulin dimers, inhibiting assembly of microtubules. Where do you predict that vincristine stops the cell cycle? - Metaphase 49) The yeast Saccharomyces cerevisiae produces haploid cells of two mating types, a and α, which are morphologically similar. Cells of opposite mating types can mate. Saccharomycescerevisiae is a(n) species. - isogamous 50) A diploid organism that you are studying has 17 pairs of chromosomes. How many total chromosomes are found in a somatic cell from this organism? A sperm cell? An egg cell? - 34; 17; 17 51) Check all that apply. Sister chromatids are separated during anaphase of mitosis. meiosis II Hartwell Chapter 4 The Chromosome Theory of Inheritance 1) Which types of chromosomes provide the basis for sex determination in most mammals? - sex chromosomes 2) In Drosophila virilis, somatic cell nuclei contain 12 chromosomes while sperm nuclei contain only 6 chromosomes. What does n equal for this species? - 6 3) The stage of mitosis when chromosomes condense to form rod-shaped structures visible under the microscope is called - prophase 4) The stage of mitosis when sister chromatids separate from each other and migrate to opposite poles of a cell is called - anaphase. 5) During which of the following stages of the cell cycle would a chromosome consist of only a single chromatid? - G1 6) Which of the following statements applies to homologous nonsister chromatids? - They contain the same genes in the same order but may have different alleles of some genes. 7) Drosophila melanogaster has four pairs of chromosomes (including a pair of sex chromosomes). Sperm from this species are formed by a meiotic process in which homologous chromosomes pair and segregate but do not undergo crossing-over. How many genetically different kinds of sperm could be produced by a Drosophila melanogaster male (XY)? - 16 8) Nondisjunction can occur at either the first or second division of meiosis. XYY individuals would most likely arise from nondisjunction at the meiotic division in the . - second; father 9) Nondisjunction can occur at either the first or second division of meiosis. XXY individuals could arise from nondisjunction at the meiotic division in the . - More than one of the choices could give rise to XXY individuals. 10) Crossing-over between homologous chromosomes occurs at which of the following stages of meiosis? - prophase I 11) Humans have 22 pairs of autosomes plus one sex chromosome pair. How many autosomes are present in a normal human primary spermatocyte? - 46 12) Premeiotic germ cells that divide mitotically in females are - oogonia. 13) The cells that undergo meiosis in males are - spermatocytes. 14) A chromosome with two arms of similar length is referred to as - metacentric. 15) At which of the following stages of meiosis would homologous chromosomes be paired? - both prophase of meiosis I and metaphase of meiosis I 16) Which of the following events occurs during mitosis but not during meiosis? A) Sister chromatids segregate. B) Homologous chromosomes pair. C) Crossing-over occurs between homologous chromosomes. D) Chromosomes align on the metaphase plate. None of the choices is correct. 17) The mitotic stage during which chromosomes begin attaching to spindle fibers and moving randomly and reversibly to the centrosomes is - prometaphase. 18) The chromosomal structure to which spindle fibers attach during the mitotic divisions is the - kinetochore. 19) Microtubules that originate at opposite centrosomes and interdigitate near the cell's equator without attaching to chromosomes are the - polar microtubules. 20) Mitosis results in chromosome number, whereas meiosis results in chromosome number. - no change in; a reduction by half in 21) Cells in the G0 stage - are in an extended G1 phase and no longer dividing. 22) Cells in the G2 stage of the cell cycle have as cells of the same species in the G1 stage. - twice as many chromatids 23) Normal fruit flies have red eyes. Flies with mutations that block the function of the X-linked white gene have white eyes. The wild-type allele is completely dominant to mutant alleles. A cross between a white-eyed female fruit fly and a red-eyed male would generate which of the following types of progeny? - red-eyed females and white-eyed males 24) Red-green color blindness is controlled by an X-linked gene in humans. The allele that causes color blindness is recessive to the allele for normal vision. A man and woman both withnormal vision had color-blind fathers. If this man and woman have a child, what is the probability that the child will be color blind? - 1/4 25) Hemophilia is caused by an X-linked recessive mutation in humans. If a woman whose paternal uncle (father's brother) was a hemophiliac marries a man whose brother is also a hemophiliac, what is the probability that their first child will have hemophilia? (Assume that no other cases of hemophilia and no hidden carriers exist in the pedigree.) - 0 26) Normal fruit flies have red eyes. Flies with mutations that block the function of the X-linked white gene have white eyes. The wild-type allele is completely dominant to mutant alleles. A white-eyed female fruit fly is mated to a red-eyed male. One of their hundreds of female progeny is white-eyed. What is the likely karyotype of this white-eyed daughter? - XXY 27) Normal fruit flies have red eyes. Flies with mutations that block the function of the X-linked white gene have white eyes. The wild-type allele is completely dominant to mutant alleles. A white-eyed female fruit fly is mated to a red-eyed male. One of their hundreds of female progeny is white-eyed. This white-eyed daughter likely arose from nondisjunction of the sex chromosomes during in the . - meiosis I or II; mother 28) Males with one copy of an X-linked gene are said to be for that gene. - hemizygous 29) In chickens, females have two different sex chromosomes (Z and W), while the males have two Z chromosomes. A Z-linked gene controls the pattern of the feathers, with the dominant B allele causing the barred pattern and the b allele causing nonbarred feathers. Which of the following crosses would produce all daughters of one type (barred or nonbarred) and all sons of the other type? - barred females × nonbarred males 30) Suppose you discover a new species of worm that exists in two forms—slimy and nonslimy. You find that mating slimy females to nonslimy males produces offspring consisting of slimy males and nonslimy females, whereas mating nonslimy females with slimy males produces offspring of both sexes that are all slimy. You would conclude that the allele is dominant and that are the heterogametic sex (the sex with two different sex chromosomes) in this species of worm. - slimy; females 31) Which of the following is not a property of homologous chromosomes? - Their centromeres are attached to each other during G2 of the cell cycle. 32) Suppose you discover a mouse that has spiky fur instead of the usual soft fur. You notice that this trait seems to be present only in males. To investigate this pattern, you cross a spiky-fur male with a soft-fur female, and find that all the F1 progeny of both sexes have soft fur. You then interbreed the F1 and observe that all the F2 females have soft fur, but 1/4 of the F2 males have spiky fur. You conclude that the spiky allele is - autosomal recessive with sex-influenced expression. 33) In fruit flies, brown eyes can be caused by recessive mutant alleles of any one of three genes: pn (prune), bw (brown) or ry (rosy). The pn gene is X-linked, bw is on the second chromosome, and ry is on the third chromosome. One wild-type allele of each of the three genes must be present for eyes to be red (wild type). Suppose that two brown-eyed flies are crossed and their progeny consist of brown-eyed sons and red-eyed daughters. Which mutation is responsible for the brown eyes in the parental female? - pn 34) Color vision depends on dominant alleles of three different genes: the R gene and the G gene, both on the X chromosome, and the B gene, which is autosomal. Recessive mutant alleles of any one of these three genes can cause color blindness in homozygotes. Suppose a color-blind man marries a color-blind woman and all their offspring have normal vision. What is the genotype of the woman? - RR GG bb 35) A variable trait in corn is the presence or absence of knobs at particular sites on some chromosomes. The allele present on each chromosome determines whether or not that chromosome has a knob. Suppose that one member of each of two pairs of homologs in a corn plant has a knob. If this plant is crossed with a knobless plant, what percentage of the offspring is expected to have only knobless chromosomes? - 25% 36) What aspect of chromosome behavior most clearly accounts for Mendel's law of segregation? - movement of homologous chromosomes to opposite poles at anaphase I of meiosis 37) What aspect of chromosome behavior most clearly accounts for Mendel's law of independent assortment? - independent alignment of different homologous pairs on the metaphase I spindle 38) Which aspect(s) of chromosome behavior is/are primarily responsible for the tremendous amount of genetic variability associated with sexual reproduction? - both crossing-over between homologous chromosomes during prophase I of meiosis and independent alignment of different homologous pairs on the metaphase I spindle 39) Which sex chromosomes are present in only one sex? - Y and W 40) In the following pedigree, the indicated trait is most likely caused by which type of allele? - X-linked recessive 41) In the following pedigree, the indicated trait most likely is caused by which type of allele? - X-linked dominant 42) In the following pedigree, the indicated trait is most likely caused by which type of allele? - autosomal dominant 43) In the following pedigree, the indicated trait is most likely caused by which type of allele? - autosomal recessive 44) In the following pedigree, the indicated trait is caused by what type of allele? - Y-linked 45) In fruit flies, an X-linked dominant mutant allele of the Notch gene (N) causes Notched wings in heterozygous females but is lethal in hemizygous or homozygous condition. What ratiooI f offspring would be observed in a cross of a Notched-wing female with a normal male? - 1/3 Notched-wing females, 1/3 normal females, 1/3 normal males 46) What is the correct order of these mitotic events? A Chromosomes align on the midplate of the cell. B Kinetochores begin attaching to spindle fibers. C Nuclear membrane reforms and chromosomes decondense. D Chromosomes condense and centrosomes migrate to opposite sides of nucleus. E Sister chromatids separate and move to opposite poles. - DBAEC 47) What is the correct order of these meiotic events? A Segregation of homologous chromosomes to opposite poles. B Segregation of sister chromatids to opposite poles. C Alignment of homologous pairs on the midplate of the cell. D Pairing and synapsis of homologous chromosomes. E Condensation of chromosomes in a diploid nucleus. - EDCAB 48) A diploid cell with three pairs of chromosomes has the genotype Aa Bb Cc, where each gene is on a different chromosome. If this cell were to undergo meiotic division, how many genetically different types of gametes could be produced? - 8 49) A cell with three pairs of chromosomes has the genotype Aa Bb Cc, with each locus on a different chromosome. If this cell were to undergo mitotic division, how many genetically different types of daughter cells could be produced? - 1 50) In humans, XO individuals are females with Turner syndrome and XXY individuals are males with Klinefelter syndrome. Which of the following events cannot give rise to a Klinefelter male? - nondisjunction at meiosis II in the father 51) In humans, XO individuals are females with Turner syndrome and XXY individuals are males with Klinefelter syndrome. Red-green color blindness is caused by an X-linked recessiveallele. Suppose a color-blind man and a woman with normal vision and no family history of color blindness married and had a daughter who was color blind and had Turner syndrome. Which event could have given rise to this offspring? - nondisjunction at either meiosis I or meiosis II in the mother 52) Individuals with an XXY karyotype are in humans and in fruit flies. - male; female 53) In animal gametogenesis, a single primary spermatocyte generates sperm, while a single primary oocyte generates egg(s). - 4; 1 54) In which of the following cases will a Barr body be seen? - both XX and XXY 55) You examine cells with a microscope and detect two Barr bodies in each cell. What is the most likely genotype of the cells? - XXX 56) You engineer an XY mouse in which the SRY gene is inactivated. What do you expect to observe in this mouse? - The mouse will develop female anatomic features. 57) An XY individual with a loss-of-function mutation in the SRY gene is expected to be female. - Answer: TRUE 58) In human oogenesis, how many chromosomes does a primary oocyte carry? - 46 59) In human oogenesis, how many chromosomes does an oogonium carry? - 46 60) In human oogenesis, how many chromosomes does a secondary oocyte carry? - 23 61) In human oogenesis, how many chromosomes does an ovum carry? - 23 62) Suppose you discovered a new mutation in mice that causes a curved spine. You noticed that this mutant phenotype is present only in females. When curved-spine females are crossed with normal males, the progeny are always recovered in a 1:1:1 ratio of curved-spine females, normal females, and normal males. Explain the genetic basis for this ratio. - hemizygous or homozygous lethal sex-linked allele Explanation: The gene is X-linked; the curved-spine allele is dominant to the normal allele in heterozygotes but is lethal in hemizygous males. 63) Which of the following statements is FALSE? A) Sister chromatids of the same chromosome are identical. B) Sister chromatids can be nonhomologous chromosomes. (FALSE) C) Homologous chromosomes are not necessarily identical. D) An example of a nonhomologous chromosome pair is paternal chromosome 1 and paternal chromosome 2 in a human. 64) At which phase of the cell cycle are sister chromatids generated? - S 65) Individuals with Turner syndrome have which of the following sex chromosome complements? - XO 66) Which term describes chromosomes whose centromeres are located closer to one end of the chromosome? - acrocentric