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1. In snapdragons, red flower color (CR) is incompletely dominant to white flower color (Cw) ; the heterozygote has pink flowers. Also, normal broad leaves (LB) are incompletely dominant to narrow, grasslike leave (LN); the heterozygote has an intermediate leaf breadth. If a red-flowered, narrow-leafed snapdragon is crossed with a white-flowered, broad-leafed one, what will be the phenotypes of the F1 and F2 generations, and what will be the frequencies of the different classes? 2. In snapdragons, red flower color (CR) is incompletely dominant to white flower color (Cw) ; the heterozygote has pink flowers. Normal-shape flowers (N) are completely dominant to peloricshaped ones (n); and tallness (T) is completely dominant to dwarfness (t). Three gene pairs segregate independently. If a homozygous red, tall, normal-flowered plant is crossed with a homozygous white, dwarf, peloric-flowered one, what proportion of the F2 plants will resemble the F1 plants in appearance? 3. In rabbits, C = agouti coat color, cch – chinchilla, ch = Himalayan, and c = albino. The four alleles constitute a multiple allelic series. The agouti C is dominant to the other three alleles, c is recessive to the other three alleles, and chinchilla is dominant to Himalayan. Determine the phenotypes of progeny from the following crosses: a. C/C x c/c b. C/cch x C/c c. C/c x C/c d. C/ ch x ch/c e. C/ ch x c/c 4. In humans, the three alleles IA, IB, and i constitute a multiple allelic series that determines the ABO blood group system, as described in this chapter. For the following problems, state whether the child mentioned can be produced, and explain your answer: a. An O child by a mating of two A individuals b. An O child by an A and a B mating c. An AB child by an A and O mating d. An O child by an AB and an A mating e. An A child by an AB and a B mating 5. A woman of blood group AB marries a man of blood group A whose father was of group O. What is the probability that … a. their two children will both be of group A? b. one child will be of group B, the other of group O? c. the first child will be a son of group AB and the second child a son of group B? 6. In guinea pigs, short hair (L) is dominant to long hair (l), and the heterozygous conditions of yellow coat (Cy) and white coat (Cw) give cream coat. A short-haired, cream guinea pig is bred to a long-haired, white guinea pig, and a long-haired, cream baby guinea pig is produced. When the baby grows up, it is bred back the short-haired, cream parent. What phenotypic classes, and in what proportions, are expected among the offspring? 7. The shape of radishes may be long (SL/SL), oval (SL/Ss), or round (Ss/Ss), and the color of radishes may be red (CR/CR), pink (CR/CW), or white (CW/CW). If a long red radish plant is crossed with a round, white plant, what will be the appearance of the F1 and F2 plants? 8. In peaches, fuzzy skin (F) is completely dominant to smooth (nectarine) skin (f), and the heterozygous condition of oval glands at the base of the leaves (GO) and no glands (GN) gives round glands. A homozygous fuzzy, no-gland peach variety is bred to a smooth, oval-gland variety. A. What will be the appearance of the F1 peaches? B. What will be the appearance of the F2 peaches? C. What will be the appearance of the offspring of a cross of the F1 peaches back to that smooth, oval-glanded parent? 9. In sheep, white fleece (W) is dominant to black (w) and horned (H) is dominant to hornless (h). A horned white ram is bred to the following four ewes and has one offspring by the first three and two by the fourth: Ewe A is hornless and black; the offspring is a horned white female. Ewe B is hornless and white; the offspring is a hornless black female. Ewe C is horned and black; the offspring is a horned white female. Ewe D is hornless and white; the offspring are one hornless black male and one horned white female. What are the genotypes of the five parents? 10. In sheep, white fleece (W) is dominant to black (w) and horned (H) is dominant to hornless (h). A horned white ewe produces the following offspring: Of the males, ¼ are horned, white: ¼ are horned, black; ¼ are hornless, white; and ¼ are hornless, black. Of the females, ½ are hornless and black, and ½ are hornless and white. What are the genotypes of the parents? 11. In shorthorn cattle, the heterozygous condition of the alleles for red coat color (CR) and white coat color (Cw) is a roan coat color. What progeny would result from the cross of a roan bull and a a. roan cow. b. red cow. c. white cow.