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In a large metropolitan hospital, cells from newborn babies are collected and examined microscopically over a 5-year period. Among approximately 7500 newborn males, six have one Barr body in the nuclei of their somatic cells. All other newborn males have no Barr bodies. Among 7500 female infants, four have two Barr bodies in each nucleus, two have no Barr bodies, and the rest have one. What is the cause of the unusual number of Barr bodies in a small number of male and female infants?
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- Given the karyotype shown at right, is this a male or a female? Normal or abnormal? What would the phenotype of this individual be?arrow_forwardIn the following schematic drawing of a Holliday junction,one chromatid is shown in red, and the homologous chromatidis shown in blue. The red chromatid carries a dominant allelelabeled A and a recessive allele labeled b, whereas the blue chromatidcarries a recessive allele labeled a and a dominant allelelabeled B. Where would the DNA strands have to be cut to produce recombinantchromosomes? Would they be cut at sites 1 and 3, or at sites2 and 4? What would be the genotypes of the two recombinantchromosomes?arrow_forwardA typical somatic cell from a badger, which is a diploid, sexually reproducing animal, contains a total of 32 chromosomes. Gametogenesis in badgers is similar to humans. What is the genome size for the badger in terms of chromosome number? How many DNA molecules would be found in a secondary oocyte before dividing? How many chromosomes would be found in a cell at metaphase? How many DNA molecules should be in a tetraploid liver cell from the badger?arrow_forward
- In Brinjal eggplants, purple fruit is incompletely dominant to white fruit, with the heterozygote being light violet. What is/are the genotype(s) of: the megaspore mother cell of a plant with purple flowers? the polar nucleus of a plant with light violet flowers? the megasporocyte of a plant with white flowers? the companion cell of a plant with light violet flowers?arrow_forwardLet’s say there is an organism with two pairs of alleles, W/w and Z/z, each pair is located on a different pair of chromosomes in the organism’s somatic cells. During Prophase, what will you observe in the somatic cells?arrow_forwardConsider the following two meiocytes in metaphase I, with crossover positions as indicated for cell A. Solid black lines indicate spindle microtubules. Assume blue chromosomes represents paternal chromosomes and green maternal chromosomes. i) How many chromosomes and chromatids were present in cell A during the G1 phase? Please clearly specify chromosomes and chromatids in your answer. ii) For cell A, list all the gametes that will be produced from this cell. Give the alleles of each gamete contained within a set of brackets. You may ignore independent assortment.iii) For cell B, list all the gametes that will be produced from this cell given crossing over. Give the alleles of each gamete contained within a set of brackets. You may assume that no crossing over would take place.arrow_forward
- The Xg cell-surface antigen is coded for by a gene located on the X chromosome. No equivalent gene exists on the Y chromosome. Two codominant alleles of this gene have been identified: Xg1 and Xg2. A woman of genotype Xg2/Xg2 bears children with a man of genotype Xg1/Y, and they produce a son with Klinefelter syndrome of genotype Xg1/Xg2Y. Using proper genetic terminology, briefly explain how this individual was generated. In which parent and in which meiotic division did the mistake occur?arrow_forwardWhy is the difference in cohesin cleavage in mitosis and meiosis important for proper segregation in each respective cell division?arrow_forwarda. Manually, using a pencil, draw a cell in anaphase II from an organism in which 2n = 2 and each chromosome is metacentric. b. Given that each G1 nucleus from this organism contains 16 picograms of DNA, how many picograms of chromosomal DNA would you expect in the cell shown here?arrow_forward
- Given the karyotype shown at right, is this a male or a female? Normal or abnormal? What would the phenotype of this individual be?arrow_forwardIn corn, male sterility is controlled by maternal cytoplasmic elements. This phenotype renders the male part of corn plants (i.e. the tassel) unable to produce fertile pollen; the female parts, however, remain receptive to pollination by pollen from male-fertile corn plants. However, the presence of a nuclear fertility restorer gene F restores fertility to male-sterile lines. Using the following color-coded circles, simulate the crosses indicated below. Put the illustrations of crosses in the spaces provided. Be sure to include in the labels the genotypes and phenotypes of the offspring in each cross. Big light green circle - male-sterile cytoplasm Big orange circle - male-fertile cytoplasm Small orange circle - FF nucleus Small half-light green-half-orange circle - Ff nucleus Small light-green circle - ff nucleusarrow_forwardA diploid species has 3 pairs of chromosomes in its somatic cells. In males, the first pair is large submetacentric[1]; the second is medium acrocentric[2], and the third is small telocentric[3]. In females, the first two pairs are like those of the males while the third is large metacentric[4][5], with satellite4 Illustrate the karyograms (drawing/picture of the chromosome) of the following: A triploid cell in females tetrasomic cell in males tetraploid cell in females [1] submetacentric --centrosome is just above the middle of the chromosome [2] acrocentric --centrosome is much higher location than submetacentric so that the “p” arm of the chromosome is much shorter than the q arm [3] telocentric --the centromere is at the end of the chromosome [4] metacentric --centrosome is in the middle of the chromosome; thus the “p-arm” and the “q-arm” or both arms of the chromosome are equal in length [5] satellite-a constriction in an arm of a chromosome, aside…arrow_forward
- Human Heredity: Principles and Issues (MindTap Co...BiologyISBN:9781305251052Author:Michael CummingsPublisher:Cengage Learning