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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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- A 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_forwardA diploid cell has 15 picograms of DNA in G₁ phase. If this cell is a germ line cell that undergoes meiosis, how much DNA will each daughter cell contain at the end of meiosis I? How much DNA will each daughter cell contain at the end of meiosis II? MI = 30 pg: MII = 15 pg O MI = 15 pg; MII = 15 pg MI = 7.5 pg; MII = 15 pg O MI = 15 pg: MII = 7.5 pgarrow_forwardThe 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_forward
- A 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_forwardDuring growth, can a patch of tissue with a white phenotype give rise to a patch with a green phenotype? Explain.arrow_forwardA couple planning their family are aware that through the past three generations on the husband’s side a substantial number of stillbirths have occurred and several malformed babies were born who died early in childhood. The wife has studied genetics and urges her husband to visit a genetic counseling clinic, where a complete karyotype-banding analysis is performed. Although the tests show that he has a normal complement of 46 chromosomes, banding analysis reveals that one member of the chromosome 1 pair (in group A) contains an inversion covering 70 percent of its length. The homolog of chromosome 1 and all other chromosomes show the normal banding sequence. (a) How would you explain the high incidence of past stillbirths? (b) What can you predict about the probability of abnormality/ normality of their future children? (c) Would you advise the woman that she will have to bring each pregnancy to term to determine whether the fetus is normal? If not, what else can you suggest?arrow_forward
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- Human Heredity: Principles and Issues (MindTap Co...BiologyISBN:9781305251052Author:Michael CummingsPublisher:Cengage Learning