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In chickens, the Leghorn variety has white feathers due to an autosomal dominant allele. Silkies have white feathers due to a recessive allele in a second (different) gene. If a true-breeding white Leghorn is crossed to a true-breeding white Silkie, what is the expected
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Genetics: Analysis and Principles
- The long hair of Persian cats is recessive to the short hair of Siamese cats, but the black coat color of Persians is dominant to the brown-and-tan coat color of Siamese. Make up appropriate symbols for the alleles of these two unlinked loci. If a pure black, long-haired Persian is mated to a pure brown-and-tan, short-haired Siamese, what will be the appearance of the F1 offspring? If two of these F1 cats are mated, what is the chance that along-haired, brown-and-tan cat will be produced in the F2 generation? (Use the shortcut probability method to obtain your answer; then check it with a Punnett square.)arrow_forwardThe recessive allele s causes Drosophila to have small wings, and the s+ allele causes normal wings. This gene is known to be X linked. If a small-winged male is crossed with a homozygous wild-type female, what ratio of normal to small-winged flies can be expected in each sex in the F1? If F1 flies are intercrossed, what F2 progeny ratios are expected? What progeny ratios are predicted if F1 females are backcrossed with their father?arrow_forwardA genotypically wild-type fruit fly is crossed to a fly with homozygous recessive mutations in two different genes that result in a wingless and an eyeless phenotype. The F1 generation is 100% phenotypically wild type. Two of the phenotypically wild-type F1 flies are mated and the following offspring are observed in the F2 generation: Wild type: 367 Wingless (wg): 119 Eyeless (ey): 134 Eyeless, wingless (ey; wg): 52 Part 1 Assuming independent assortment, how many F2 offspring would be expected to be homozygous for the wingless mutation but have normal eyes? O224 O126 O 112 O 378 Part 2 How many degrees of freedom are there in the results of this cross? O0 O 1 02 03 O4arrow_forward
- In the rat, the pattern of coat color is affected by a gene with two alleles. PH is the allele for hooded, in which the animal is mostly white with color restricted to the shoulders and neck. P+ is the normal solid body color allele. These two alleles exhibit incomplete dominance, so that heterozygotes have white bellies only. A true-breeding solid strain is crossed with a true-breeding hooded strain, to produce an F₁ generation that is all white belly. The F₁ generation rats are mated with each other to produce 800 F₂ offspring. Below is a table that gives the observed number of each phenotype in the F2 and also gives you the expected number. Question: If you perform a Chi-square goodness of fit test, what is the value of Chi square X² (Express your answer to the hundredths.) solid white belly hooded Σ Observed 195 420 185 800 Expected 200 400 200 800arrow_forwardA certain plant species has dominant red flower color (R) to the recessive white flower color (r). A pure breeding (homozygous) red-flowering plant is crossed with a pure breeding white-flowering plant. What are the possible outcomes for the F1 generation? (Show the Punnett squarearrow_forwardA female fruit fly with vermilion eyes and normal wings is crossed with a male with normal red eyes and cut wings. The F₁ progeny consist of females with red eyes and normal wings, and males with vermilion eyes and normal wings. When the F₁ progeny are interbred, the F2 consists of two types of females-vermilion eyes, normal wings (1/2) and red eyes, normal wings (1/2), and two types of males- vermilion eyes, normal wings (1/2) and red eyes, cut wings (1/2). Are the genes for eye colour and wing type X-linked or autosomal? Both genes are X-linked. The eye-colour gene is X-linked and the wing-type gene is autosomal. The eye-colour gene is autosomal and the wing-type gene is X-linked. Both genes are autosomal. More than one of the choices is consistent with the data.arrow_forward
- Two genes control color in corn snakes as follows:O– B– snakes are brown, O– bb are orange, oo B– areblack, and oo bb are albino. An orange snake wasmated to a black snake, and a large number of F1progeny were obtained, all of which were brown.When the F1 snakes were mated to one another, theyproduced 100 brown offspring, 25 orange, 22 black,and 13 albino.a. What are the genotypes of the F1 snakes?b. What proportions of the different colors wouldhave been expected among the F2 snakes if the twoloci assort independently?arrow_forwardIn cabbage butterflies, White wings are dominant to yellow wings. If a heterozygous white-winged butterfly is crossed with a yellow-winged butterfly, what are the possible genotypes and phenotypes of the offspring and the percent chance for each?arrow_forwardA parental cross between homozygous wild-type red eyed females (X+ X+) were crossed with white eyed males (XwY). The F1 generation consisted of phenotypic X+Xw females and X+Y males. The F2 generation was produced by crossing the F1 generation and consisted of a ratio of 2 red eyed females (X+ X+ and X+ Xw) : 1 red eyed male (X+Y) : 1 white eyed male (XwY). Attached is a picture of a chi square analysis based on the results from the F2 generation. Please discus what conclusions can be made based on the data/findings. What inheritance pattern is this?arrow_forward
- In a species of bird, feather colour is determined by a single, non-autosomal gene that shows complete penetration. A red-feathered female mates with a blue-feathered male, and all the F1 males are blue-feathered and the F1 females are red-feathered. When the F1 individuals are crossed, all the F2 males are again blue-feathered and the F1 females are again red- feathered. Provide the genotype of the F2 males and females. Clearly indicate which genotype is associated with males and females, respectively. Binomial Expansion 1 a+b 2 a' + 2ab + b? 3 a'+ 3a'b + 3ab + b a + 4a'b + 6a'b + 4ab + b 5 a + Sa*b + 10a'b2 + 100'b + Sab + barrow_forwardIn some sheep, horns are produced by an autosomal allele that is dominant in males and recessive in females. A horned female is crossed with a hornless male. One of the resulting F1 females is crossed with a hornless male. What proportion of the male and female progeny from this cross will have horns?arrow_forward) Radish flowers may be red, purple, or white. A cross between a red-flowered plant and a white-flowered plant yields all-purple offspring. The part of the radish we eat may be oval or long, with long being the dominant trait. If true-breeding red-flowered long radishes are crossed with true-breeding white-flowered oval radishes, what would the F1 generations genotype and phenotype be For full credit, you must show all work.arrow_forward
- Human Biology (MindTap Course List)BiologyISBN:9781305112100Author:Cecie Starr, Beverly McMillanPublisher:Cengage Learning