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A dark-red strain and a white strain of wheat are crossed and produce an intermediate, medium-redF1. When the F1 plants are interbred, an F2 generation is produced in a ratio of 1 dark-red: 4 medium-dark-red: 6 medium-red: 4 light-red: 1 white. Further crosses reveal that the dark-red and white F2 plants are true breeding.
(a) Based on the ratios in the F2 population, how many genes are involved in the production of color?
(b) How many additive alleles are needed to produce each possible phenotype?
(c) Assign symbols to these alleles and list possible genotypes that give rise to the medium-red and light-red
(d) Predict the outcome of the F1 and F2 generations in a cross between a true-breeding medium-red plant and a white plant.
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Essentials of Genetics (9th Edition) - Standalone book
- A dark-red strain and a white strain of wheat are crossed and produce an intermediate, medium-red F1. When the F1 plants are interbred, an F2 generation is produced in a ratio of 1 dark-red: 4 medium-dark-red: 6 medium-red: 4 light-red: 1 white. Further crosses reveal that the dark-red and white F2 plants are true breeding. Predict the outcome of the F1 and F2 generations in a cross between a true-breeding medium-red plant and a white plant.arrow_forwardTwo true-breeding varieties of maize, one 11 cm high and the other 47 cm high were crossed and the resultant F1 hybrids were then crossed to generate the F2 . In the F2 there were a total of 13,923 plants with a continuous variation in heights between the two extremes and with only 3 plants as large as 47 cm high and 5 plants of 11 cm high. a) How many i) genes and ii) how many alleles are involved in determining height in this plant?arrow_forwardTwo true-breeding varieties of maize, one 11 cm high and the other 47 cm high were crossed and the resultant F1 hybrids were then crossed to generate the F2 . In the F2 there were a total of 13,923 plants with a continuous variation in heights between the two extremes and with only 3 plants as large as 47 cm high and 5 plants of 11 cm high. a) How many i) genes and ii) how many alleles are involved in determining height in this plant? b) What is the contribution of each dominant allele to the phenotype in cm? c) What would be the size and genotype of the F1 from a cross between a true-breeding 11 cm plant and a true-breeding 47 cm plant? d) The F1 from (b) is then crossed to give an F2. What proportion would you expect in the F2 of each extreme phenotype? e) In a cross between a 29cm plant and a 20cm plant what would be the genotypes giving the smallest number of different phenotypes? specify the phenotypes observed. Please answer the following problem & EXPLAIN your answer…arrow_forward
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- 1) Two true-breeding varieties of maize, one 11 cm high and the other 47 cm high were crossed and the resultant F1 hybrids were then crossed to generate the F2 . In the F2 there were a total of 13,923 plants with a continuous variation in heights between the two extremes and with only 3 plants as large as 47 cm high and 5 plants of 11 cm high.a) How many i) genes and ii) how many alleles are involved in determining height in this plant? b) What is the contribution of each dominant allele to the phenotype in cm? c) What would be the size and genotype of the F1 from a cross between a true-breeding 11 cm plant and a true-breeding 47 cm plant? d) The F1 from (b) is then crossed to give an F2. What proportion would you expect in the F2 of each extreme phenotype? e) In a cross between a 29cm plant and a 20cm plant what would be the genotypes giving the smallest number of different phenotypes? specify the phenotypes observed.arrow_forward1) Two true-breeding varieties of maize, one 11 cm high and the other 47 cm high were crossed and the resultant F1 hybrids were then crossed to generate the F2 . In the F2 there were a total of 13,923 plants with a continuous variation in heights between the two extremes and with only 3 plants as large as 47 cm high and 5 plants of 11 cm high. a) What would be the size and genotype of the F1 from a cross between a true-breeding 11 cm plant and a true-breeding 47 cm plant? b) The F1 from (b) is then crossed to give an F2. What proportion would you expect in the F2 of each extreme phenotype? c) In a cross between a 29cm plant and a 20cm plant what would be the genotypes giving the smallest number of different phenotypes? specify the phenotypes observed.arrow_forwardTwo true-breeding varieties of maize, one 11 cm high and the other 47 cm high were crossed and the resultant F1 hybrids were then crossed to generate the F2 . In the F2 there were a total of 13,923 plants with a continuous variation in heights between the two extremes and with only 3 plants as large as 47 cm high and 5 plants of 11 cm high. How many genes and how many alleles are involved in determining height in this plant?arrow_forward
- The height of the seed head in wheat at maturity is determined by several genes. In one variety, the head is just 9 inches above the ground; in another, it is 33 inches above the ground. Plants from the 9-inch variety were crossed to plants from the 33-inch variety. Among the F1, the seed head was 21 inches above the ground. After self-fertilization, the F1 plantsproduced an F2 population in which 9-inch and 33-inch plants each appeared with a frequency of 1/256. (a) How many genes are involved in the determination of seed head height in these strains of wheat? (b) How much does each allele of these genes contribute toseed head height? (c) If a 21-inch F2 plant were crossed to a 9-inch plant, how often wouldyou expect 18-inch wheat to occur in the progeny?arrow_forwardTwo true-breeding varieties of maize, one 11 cm high and the other 47 cm high were crossed and the resultant F1 hybrids were then crossed to generate the F2. In the F2 there were a total of 13,923 plants with a continuous variation in heights between the two extremes and with only 3 plants as large as 47 cm high and 5 plants of 11 cm high. In a cross between a 29cm plant and a 20cm plant what would be the genotypes giving the smallest number of different phenotypes? specify the phenotypes observed.arrow_forwardTwo true-breeding varieties of maize, one 11 cm high and the other 47 cm high were crossed and the resultant F1 hybrids were then crossed to generate the F2 . In the F2 there were a total of 13,923 plants with a continuous variation in heights between the two extremes and with only 3 plants as large as 47 cm high and 5 plants of 11 cm high.SO In a cross between a 29cm plant and a 20cm plant what would be the genotypes giving the smallest number of different phenotypes? specify the phenotypes observed.arrow_forward
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