7. The dominant allele H reduces the number of body bristles in fruit flies, giving rise to a hairless phenotype. In the homozygou condition, H is lethal. The dominant allele S has no effect on bristle number except in the presence of H, in which case a single S allele suppresses the hairless phenotype, thus restoring the bristles. However, S is also lethal in homozygotes. a. What ratio of flies with normal bristles to hairless individuals would we find in the live progeny of a cross between two normal flies both carrying the H allele in the suppressed condition? b. When the hairless progeny of the previous cross are crossed with one of the parental normal flies from part (a) (meaning a fly that carries H in the suppressed condition), what phenotypic ratio would you expect to find among their live progeny?

7. The dominant allele H reduces the number of body bristles in fruit flies, giving rise to a hairless phenotype. In the homozygou condition, H is lethal. The dominant allele S has no effect on bristle number except in the presence of H, in which case a single S allele suppresses the hairless phenotype, thus restoring the bristles. However, S is also lethal in homozygotes. a. What ratio of flies with normal bristles to hairless individuals would we find in the live progeny of a cross between two normal flies both carrying the H allele in the suppressed condition? b. When the hairless progeny of the previous cross are crossed with one of the parental normal flies from part (a) (meaning a fly that carries H in the suppressed condition), what phenotypic ratio would you expect to find among their live progeny?

Name: 7. The dominant allele H reduces the number of body bristles in fruit
Uploaded: 2024-03-20T06:43:04.000Z
Channel: Bartleby
Description: 7. The dominant allele H reduces the number of body bristles in fruit flies, giving rise to a hairless phenotype. In the homozygoucondition, H is lethal. The dominant allele S has no effect on bristle number except in the presence of H, in which cas

Biology: The Unity and Diversity of Life (MindTap Course List)

14th Edition

ISBN:9781305073951

Author:Cecie Starr, Ralph Taggart, Christine Evers, Lisa Starr

Publisher:Cecie Starr, Ralph Taggart, Christine Evers, Lisa Starr

Chapter13: Observing Patterns In Inherited Traits

Section: Chapter Questions

Problem 7GP: Several alleles affect traits of roses, such as plant form and bud shape. Alleles of one gene govern...

See similar textbooks

Similar questions

4) In frost moths, two alleles of one gene determine the character difference of spotted versus striped wings and two alleles of a separate, independent gene determine the character difference of orange wing background versus white wing background. The results for four matings of moth phenotypes are shown in the image attached. a) Assign the letter “s” to the wing pattern gene and letter “w” to the background color gene. Write in the capital letter for the dominant phenotype and the lower case letter for the recessive phenotype. Also, write whether each allele is dominant (D) or recessive (R). Wing pattern gene: Spotted - letter assignment:____ - dominant or recessive:____ Striped - letter assignment:____ - dominant or recessive:____ Background color gene: orange: - letter assignment:____ - dominant or recessive:____ white: - letter assignment:____ - dominant or recessive:_____ b) Based on the four matings in Question 4: What are the genotypes of each parent in each cross? If more…
2.In dogs, there is a hereditary deafness caused by a recessive allele, d. A kennel owner has a male dog that she wants to use for breeding purposes if possible. The dog can hear, but the owner is unsure of the genotype. She does a testcross (crosses it to a homozygous recessive dog), and two of the five offspring are deaf. This means that the male dog A.has the genotype DD B.has the genotype Dd C.is still of unknown genotype since there were offspring of both deaf and hearing phenotypes. D.has the genotype dd
1. In a particular bird species, the tips of the feathers are tinged with blue, white, or silver. The BB genotype calls for blue-tipped feathers. The WW genotype calls for white-tipped feathers. The BW genotype calls for an intermediate with silver-tipped feathers. A mating occurs between a blue-tipped bird and a white-tipped bird. What types of offspring would be expected? Give the genotypes and phenotypes of the possible offspring and the probability of each. 2. The bird species described in question 5 has an ornamental plumage on its head. The plumage feathers are either flexible or stiff. The allele for flexible plumage is dominant over the allele for stiff plumage. A male who is heterozygous for plumage and has silver-tipped wings mates with a female who has stiff plumage with silver-tipped wings. What types of offspring would be expected from this cross? Give the probability of each. 3. In some cats, the gene for tail length shows incomplete dominance. When a cat with a…
6. Consider that people with blue eyes must have two alleles for blue eyes since blue eye color is a recessive trait. A blue-eyed person and a brown-eyed person have an offspring with blue eyes. The brown-eyed person must A. have two alleles for blue eyes. B. have two alleles for brown eyes. C. not have the dominant brown eye allele. D, have one allele for blue eyes and one allele for brown eyes.
1. A woman who is heterozygous for the brown eye and blue eye alleles marries a man with blue eyes. What are the genotypes and phenotypes of the children? a) What is the genotypic ratio of the above cross (Write number next to genotype)? ___________________________________________________________________ b) What is the phenotypic ratio of the above cross? (Write number next to phenotype)? ___________________________________________________________________
1. In fruit flies, the phenotype for eye color is determined by a certain locus. E indicates the dominant allele and eindicates the recessive allele. The cross between a male wild-type fruit fly and a female white-eyed fruit flyproduced the following offspring.Wild-typeMaleWild-typeFemaleWhite-eyedMaleWhite-eyedFemaleBrown-eyedFemaleF1 0 45 55 0 1The wild-type and white-eyed individuals from the F1 generation were then crossed to produce the followingoffspring.F2 23 31 22 24 0(a) Determine the genotypes of the original parents (P generation) and explain your reasoning. You may usePunnett squares to enhance your description, but the results from the Punnett squares must be discussed inyour answer.(b) Use a Chi-squared test on the F2 generation data to analyze your prediction of the parental genotypes. Showall your work and explain the importance of your final answer.(c) The brown-eyed female in the F1 generation resulted from a mutational change. Explain what a mutation is,and discuss…
3. A couple just had a baby, who has type-O blood. Upon learning the baby’s blood type, the father becomesinfuriated and accuses the mother of cheating on him. The mother has type-A blood and the father has type-Bblood. Knowing that the allele for type-O is recessive, answer the following questions.a. What is the relationship between the IA, IB, and i alleles?b. Is the father right? Or is he falsely accusing the mother? Explain. Include the genotypes of the parentsand the genotypes of their potential children.
1.) A farmer wants to breed a variety of taller corn. a) How can the farmer use variation in the height of the current corn plants to produce taller corn plants? b) Will the farmer’s work be most effective if height in corn plants is determined by polygenic inheritance, multiple alleles, or co-dominant alleles? Explain. c) The farmer finds that many of the tallest corn plants are also very susceptible to a particular disease. How could the farmer design an experiment to find out if the genes for height are linked to the genes for resistance to the disease?
4. An albino corn snake is crossed with a normal-coloredcorn snake. The offspring are all normal-colored.When these first-generation progeny snakes arecrossed among themselves, they produce 32 normalcolored snakes and 10 albino snakes.a. How do you know that only a single gene is responsible for the color differences between these snakes? b. Which of these phenotypes is controlled by thedominant allele?c. A normal-colored female snake is involved in atestcross. This cross produces 10 normal-coloredand 11 albino offspring. What are the genotypes ofthe parents and the offspring?
1. If a set of parents both have Bb genotypes, how many different types of zygotes can they form? CHOICES: A. one. B. Two C. three.D four 2. Having black hair is represented by the following alleles: A, B, and C. Which of the following genotypes represent the alleles of having brown hair? CHOICES: A. aabbcc B. AaBbcc C. AAbbcc D. AABBCC 3. Two parents have normal vision, but their son is born colorblind. What must be the mother's genotype using XB for normal and Xb for color-blind vision? B. XBXB C. XBXb D. XbXb A. XX 4. The colorblind son grows up and marries a woman with normal vision. She does not carry the colorblind allele. Their genotypes are XbYb and XBXB,respectively. By using the Punnett square solve for the percentage of the phenotype. What is the percentage that their first child will be colorblind? CHOICES: A.0% B. 25% C. 50% D. 75% 5. Which of the following traits is NOT controlled by multiple genes? A.colorblindness C. freckles B.eye color D. hair texture
4.) A man and a woman have a child. The father is blood type A, and one of his parents was blood type A and the other was blood type O. The mother is blood type B, and one of her parents was blood type B, the other type O. Both the father and the mother are carriers of the Bombay allele. (Neither of the type-O grandparents were type O because of the Bombay allele – they had the regular type O genotype.) WhataretheoddsthattheirbabywillhavebloodtypeO? WhataretheoddsthattheirbabywillhavebloodtypeAB? (Hint – for this question, you should draw out a pedigree and fill in as much as you can for the genotypes of BOTH genes that are involved.)
4. Huntington diseases is a rare fatal, degenerative neurological disease in which individuals start to show symptoms in their 40s. It is caused by a dominant allele. Joe, a man in his 20s, just learned that his father has Huntington disease. a. What is the probability that Joe will also develop the disease?b. Joe and his new wife have been eager to start a family. What is the probability that their first child will eventually develop the disease?