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Flower color in snapdragons results from the amount of the pigment anthocyanin in the petals. Red flowers are produced by plants that have full anthocyanin production, and ivory-colored flowers are produced by plants that lack the ability to produce anthocyanin. The allele
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Genetic Analysis: An Integrated Approach (3rd Edition)
- The shape of a pumpkin is determined by the action of two genes A and B. The recessive forms of these two alleles produces a flattened-shaped fruit, whereas the dominant forms of these two alleles produce the typical pumpkin with ridges. When both alleles are heterozygous a disc-shaped pumpkin is produced. If the genotype of the pumpkin plant is homozygous dominant at one allele and heterozygous at the other, the pumpkin will be ball-shaped. If the pumpkin plant is homozygous recessive at one allele and heterozygous at the other allele it produces an oblong-shaped fruit. Plants with genotypes other than the ones listed in this question do not produce pumpkins. Do the following cross: two pumpkin plants capable of making disc-shaped pumpkins are crossed with each other. Based on this cross, answer the following: (Show your work below.) How many of the progeny will make ball-shaped pumpkins?__________________________________________ How many of the progeny will make disc-shaped…arrow_forwardIn a certain species of plant loci A, B and C have an additive effect on the colour of the flower. Alleles A, B, and C are dominant and alleles a, b and c are recessive. Knowing that a plant with genotype AAbbCc has a pink flower, which genotype, among the ones listed below, will produce the same phenotype? a. AABBCc b. AaBbCc c. Aabbcc d. aabbccarrow_forward. In garden peas, yellow (Y) seed color is dominant to green (y). Because yellow and green are two different forms of the same gene (seed color), they are alleles. Use a Punnett square to show a cross between two heterozygous pea plants. What are the phenotype(s) of the offspring? What are the genotype(s) of the offspring?arrow_forward
- A genetic engineer is going to cross two watermelon plants to produce seeds for a spring planting. He is breeding for size, and wants to have as many watermelons with the phenotype for long shape as possible. In watermelons, the allele for short shape (R) is dominant to the allele for long shape (r). Would crossing a watermelon homozygous recessive for the trait with a watermelon heterozygous for the trait give the most long watermelons possible? Explain your answer using Punnett Squares.arrow_forwardIn flies, small wings are recessive to normal wings. If a cross between two flies produces 8 small-wing offspring and 28 normal-wing offspring, what are the most likely genotypes of the parents? (Use SS to represent the normal-wing allele and ss to represent the short-wing allele.)arrow_forwardIn humans, there are three alleles for blood type: A, B, and O. A and B are codominant over O. A male with type AB blood and a female with type A blood have a child. The male’s parents both had type AB blood. The female’s mother had type A blood and her father had type B blood. What is the potential phenotype of the child? A. type A (25%), type B (25%), type AB (25%), type O (25%) B. type A (25%), type B (50%), type AB (25%) C. type A (25%), type B (25%), type AB (50%) D. type A (50%), type B (25%), type AB (25%)arrow_forward
- Kernel color in wheat Red kernel color in wheat results from the interaction between two dominant alleles. With only one dominant allele, the phenotype is brown while in the absence of any dominant allele, the phenotype is white. Suppose that plants of a variety that is true breeding for red kernels are crossed with plants true breeding for white kernels. What specific type of interaction can be observed? A. duplicate dominant genes B. duplicate genes with cumulative effects C. complementary genes D. dominant epistasis (case 2)arrow_forwardIn humans, alkaptonuria is a metabolic disorder in which affected persons produce black urine. Alkaptonouria results from an allele (a) that is recessive to the allele for normal metabolism (A). Alana has a normal metabolism, but her brother has alkaptonouria. Alana’s father has alkaptonuria. Give the genotypes of Alana _______, her mother________, her father_______, and her brother______. If Alana’s parents have another child, what is the probability that the child will have alkaptonuria?_____ If Alana marries a man with alkatonuria, what is the probability that their first child will have black urine? _______ What is the probability that 3 of their children will have black urine?__________ If Alana marries a man that does not have alkatonuria, but has a mother that does, then what is the probability that their first child will have black urine? _______ 3 children in a row? ___________arrow_forwardJ. W. McKay crossed a stock melon plant that produced tan seeds with a plant that produced red seeds and obtained the following results (J. W. McKay. 1936. Journal of Heredity 27:110–112). Cross F1 F2 tan ♀ × red ♂ 13 tan seeds 93 tan, 24 red seeds a. Explain the inheritance of tan and red seeds in this plant. b. Assign symbols for the alleles in this cross and give genotypes for all the individual plants.arrow_forward
- Sometimes, two alleles are neither dominant nor recessive, therefore, both alleles are expressed separately in a heterozygous individual. This is called codominance. Which of the following is an example of codominance? a In guinea pigs, black hair is dominant over white hair. A homozygous black guinea pig is crossed with a homozygous white guinea pig. The first generation of offspring are black. b If you cross a plant with blue flowers with a plant with yellow flowers, the offspring will have blue flowers with yellow spots. c If you cross a rhododendron plant with red flowers with a rhododendron plant with white flowers, the offspring will have pink flowers. d A white female cat mates with a brown male cat. The resulting offspring are orange.arrow_forwardAlbinism is the absence of pigment throughout the body. Animals with albinism have white fur and reddish eyes. Albinism is inherited as a recessive trait, so animals with two a alleles have albinism, whereas animals with at least one dominant A allele have normal coloring. Using the Punnett square below, determine the probability of two albino parents (with aa genotypes) producing a child with albinism.arrow_forwardIn basic eye color in humans, brown (B) is dominant to blue (b). A brown-eyed man, whose father was brown-eyed and whose mother was blue-eyed, married a blue-eyed woman whose father and mother were both brown-eyed' The couple has a blue-eyed son. For which of the individuals mentioned can you be sure of the genotypes? What genotypes are possible for the others?arrow_forward
- Human Heredity: Principles and Issues (MindTap Co...BiologyISBN:9781305251052Author:Michael CummingsPublisher:Cengage LearningHuman Biology (MindTap Course List)BiologyISBN:9781305112100Author:Cecie Starr, Beverly McMillanPublisher:Cengage Learning