Biology: The Unity and Diversity of Life (MindTap Course List)
14th Edition
ISBN: 9781305544703
Author: STARR
Publisher: Cengage
expand_more
expand_more
format_list_bulleted
Concept explainers
Videos
Textbook Question
Chapter 10, Problem 3CT
Almost all calico cats (one is pictured in FIGURE 10.7B) are female. Why?
B When this calico cat was an embryo, one of the two X chromosomes was inactivated in each of her cells. The descendants of the cells formed her adult body, which is a mosaic for expression of X chromosome genes. Black fur arises in patches where genes on the X chromosome inherited from one parent are expressed; orange fur arises in patches where genes on the X chromosome inherited from the other parent are expressed.
FIGURE 10.7 ►Animated X chromosome inactivation.
Expert Solution & Answer
Trending nowThis is a popular solution!
Students have asked these similar questions
Which of the following statements is false?
Dosage compensation is accomplished in humans by stimulation of gene expression from the single X chromosome.
Dosage compensation is accomplished in humans by inactivating a female X chomosome.
An individual with Turner Syndrome has no Barr bodies.
An individual with Klinefelter syndrome generally has one Barr body.
A typical XX human female has one Barr body.
In Drosophila, the genes for withered wings (whd), smooth abdomen (sm) and speck body (sp) are located on chromosome 2 and are separated by the following map distances:whd ----------(30.5)----------sm-----(15.5)-----spA female with withered wings and a smooth abdomen was mated to a male with a speck body.The resulting phenotypically wild-type females were mated with males that had the mutant phenotype for all three traits, producing 1000 offspring.
Calculate the number of expected double crossover progeny.
Express your answer to the nearest whole number.
One of the X chromosomes in a particular Drosophila female had a normal order of genes but carried recessive alleles of the genes for yellow body color (y), vermilion eye color (v), and forked bristles (f), as well as the dominant X-linked Bar eye mutation (B). Her other X chromosome carried the wild-type alleles of all four genes, but the region including y+, v+, and f+ (but not B+) was inverted with respect to the normal order of genes. This female was crossed to a wild- type male in the cross diagrammed her.
The cross produced the following male offspring:* table in figure
a. Why are there no male offspring with the allele combinations y v f+, v+ v+ f, y v+ f+, or y+ v f (regardless of the allele of the Bar eye gene)?b. What kinds of crossovers produced the y v f b+ and v+ y+ f+ B offspring? Can you determine any genetic distances from these classed of progeny?c. What kinds of crossovers produced the y+ v f+ B+ and y v+ f B offspring?
Chapter 10 Solutions
Biology: The Unity and Diversity of Life (MindTap Course List)
Ch. 10 - The expression of a gene may depend on _______. a....Ch. 10 - Prob. 2SQCh. 10 - Binding of ______ to _______ in DNA can increase...Ch. 10 - Prob. 4SQCh. 10 - Prob. 5SQCh. 10 - Muscle cells differ from bone cells because...Ch. 10 - Prob. 7SQCh. 10 - Homeotic gene products _______. a. flank a...Ch. 10 - A gene that is knocked out is ________. a. deleted...Ch. 10 - Which of the following includes all of the others?...
Ch. 10 - Prob. 11SQCh. 10 - Effect of Paternal Grandmothers Food Supply on...Ch. 10 - Prob. 2DAACh. 10 - Effect of Paternal Grandmothers Food Supply on...Ch. 10 - Prob. 12SQCh. 10 - A cell with a Barr body is ___ . a. a bacterium b....Ch. 10 - Operons _____. a. only occur in bacteria b. have...Ch. 10 - Prob. 15SQCh. 10 - Why are some genes expressed and some not?Ch. 10 - Prob. 2CTCh. 10 - Almost all calico cats (one is pictured in FIGURE...Ch. 10 - The photos above show flowers from Arabidopsis...
Knowledge Booster
Learn more about
Need a deep-dive on the concept behind this application? Look no further. Learn more about this topic, biology and related others by exploring similar questions and additional content below.Similar questions
- One of the X chromosomes in a particular Drosophila female had a normal order of genes but carried recessive alleles of the genes for yellow body color (y), vermilion eye color (v), and forked bristles (f), as well as the dominant X-linked Bar eye mutation (B). Her other X chromosome carried the wild-type alleles of all four genes, but the region including y+, v+, and f+ (but not B+) was inverted with respect to the normal order of genes. This female was crossed to a wild-type male in the cross diagrammed her. The cross produced the following male offspring: Y v f B 48 y+ v+ f+ B+ 45 y v f B+ 11 y+ v+ f+ B 8 y v f B 1 y+ v+ f+ B+ 1 a. Why are there no male offspring with the allele combinations y v f+, v+ v+ f, y v+ f+, or y+ v f (regardless of the allele of the Bar eye gene)? b.What kinds of crossovers produced the y v f b+ and v+ y+ f+ B offspring? Can you determine any genetic distances from these classed of progeny? c. What kinds of crossovers produced the…arrow_forwardThe coloration of calico cats is also the result of the inactivation of one of a female cat's sex chromosomes. In females, two X chromosomes are present in all cells but only one is active, the inactive one is called a BARR BODY. This is why the coat color is random, even among cloned calico cats that have identical genomes. Calico is a coat color found in cats, which is caused by a SEX-LINKED, CODOMINANT allele.arrow_forwardThe introduction to this chapter described the search for genes that determine pattern baldness in humans. In 1916, Dorothy Osborn suggested that pattern baldness is a sex-influenced trait that is dominant in males and recessive in females. More research suggested that pattern baldness is an X-linked recessive trait. Would you expect to see independent assortment between genetic markers on the X chromosome and pattern baldness if (a) pattern baldness is sexinfluenced and (b) if pattern baldness is X-linked recessive? Explain your answer.arrow_forward
- Bow-legs is hypothesized to be X-linked recessive trait in Drosophila melanogaster. The P1 virgin females were, once again, homozygous wild type but the males were bow-legged. There were 52 wild type males and 67 wild type females in the F1 generation. The F2 generation contained 30 wild type males, 75 wild type females, 40 bow-legged males and no bow-legged females. Is this what is to be expected? Use chi-square to prove your position.arrow_forwardWhat is a Barr body? How many Barr bodies in a person with genotype XXXXX? How is the structure of a Barr body different from that of other chromosomes in the cell? How does the structure of a Barr body affect gene expression? Color-blindness is an X-linked recessive trait. Heterozygous females are not color blind but they can sometimes have partial color blindness. Explain how this can occur.arrow_forwardNormal vision (XA) in humans is dominant to color blindness (Xa) and is X-linked. A man with normal vision, whose father was colorblind, marries a colorblind woman. What are the chances that a son will be colorblind? What are the chances that a daughter will be colorblind? The determiner for brown eyes (B) is dominant to blue eyes (b) and is not X-linked. A colorblind man with brown eyes, whose mother was blue-eyed, marries a blue-eyed woman having normal vision, whose father was colorblind. Show the expected phenotypes ratio of their children involving eye color, color blindness, and sex.arrow_forward
- A company that offers PGD terms an embryo “normal and healthy” if it has 46 chromosomes. Why is this statement misleading? , Two famous male actors had twins using a surrogate mother who carried two embryos that hadbeen fertilized in vitro, one with one man’s sperm and the other with the other man’s sperm. In terms of genetics, how closely are the babies, a boy and a girl, related to each other if they have different fathers?arrow_forwardWhat is a Barr body? How is its structure different from that ofother chromosomes in the cell? How does the structure of a Barrbody affect the level of X-linked gene expression?arrow_forwardIn Drosophila, one of the genes controlling wing length is located on the X chromosome. A recessive mutant allele of this gene makes the wings miniature—hence, its symbol m; the wild-type allele of this gene, m_, makes the wings long. One of the genes controlling eye color is located on an autosome. A recessive mutant allele of this gene makes the eyes brown—hence, its symbol bw; the wildtype allele of this gene, bw_, makes the eyes red. Miniature-winged, red-eyed females from one true-breeding strain were crossed to normal-winged, brown-eyed males from another true-breeding strain. 1. Predict the phenotypes of the F1 flies. 2. If these flies are intercrossed with one another, what phenotypes will appear in the F2, and in what proportions?arrow_forward
- Imagine a scenario in which prenatal testing of a human female fetus indicates that the baby will have a normal XX karyotype but is heterozygous for a mutation that inactivates the Xist promoter. Allele “Xr” represents the mutated version of the Xist promoter, and “XR” represents the normal version of the Xist promoter. How will this mutation affect the process of X inactivation?A. "X inactivation will still be random with both mutant and normal X chromosomes being randomly inactivated" B. "The chromosome with the mutant Xist promoter will always be active" C. "The chromosome with the mutant Xist promoter will always be inactivated" D. "The normal X chromosome (no mutation in Xist) will always be active" E. "The normal X chromosome (no mutation in Xist) will always be inactivated"arrow_forwardYou are studying a group of mutations in Drosophila all of which are recessive lethal and map to a small area of chromosome 3. You decide to perform complementation testing to see which mutations are in the same gene. You have bred your flies such that they have the following genotype: +; +; TM3 Sb/mut; + This indicates that chromosomes X, 2, and 4 are wild-type. One copy of chromosome 3 is the balancer TM3 Sb which carries a recessive lethal gene and the dominant marker Stubble (Sb), which causes the flies to have short bristles. The other copy of chromosome 3 carries your recessive lethal mutation. a) Describe how you would maintain each of your individual stocks. What ratios of phenotypes do you expect? b) When you perform your complementation testing, you will have to look at the F1 phenotypes to determine whether two genes complement. Describe what your F1 fly population should look like if the two mutations complement and if they do not. You breed each of your four…arrow_forwardWhy do some genes express themselves later in life? Why not earlier? How many chromosomes in a human that has trisomy-15? How many chromosomes in a human that is triploid?arrow_forward
arrow_back_ios
SEE MORE QUESTIONS
arrow_forward_ios
Recommended textbooks for you
Biology: The Unity and Diversity of Life (MindTap...BiologyISBN:9781305073951Author:Cecie Starr, Ralph Taggart, Christine Evers, Lisa StarrPublisher:Cengage Learning
Biology: The Unity and Diversity of Life (MindTap...
Biology
ISBN:9781305073951
Author:Cecie Starr, Ralph Taggart, Christine Evers, Lisa Starr
Publisher:Cengage Learning
Mitochondrial mutations; Author: Useful Genetics;https://www.youtube.com/watch?v=GvgXe-3RJeU;License: CC-BY