ESSENTIALS OF GENETICS-W/MOD.ACCESS
9th Edition
ISBN: 9780134452876
Author: KLUG
Publisher: PEARSON
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Chapter 21, Problem 6PDQ
An inbred strain of plants has a mean height of 24 cm. A second strain of the same species from a different geographical region also has a mean height of 24 cm. When plants from the two strains are crossed together, the F1 plants are the same height as the parent plants. However, the F2 generation shows a wide range of heights; the majority are like the P1 and F1 plants, but approximately 4 of 1000 are only 12 cm high, and about 4 of 1000 are 36 cm high.
(a) What mode of inheritance is occurring here?
(b) How many gene pairs are involved?
(c) How much does each gene contribute to plant height?
(d) Indicate one possible set of genotypes for the original P1 parents and the F1 plants that could account for these results.
(e) Indicate three possible genotypes that could account for F2 plants that are 18 cm high and three that account for F2 plants that are 33 cm high.
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An inbred strain of plants has a mean height of 24 cm. A second strain of the same species from a different geographic region also has a mean height of 24 cm. When plants from the two strains are crossed together, the F1 plants are the same height as the parent plants. However, the F2 generation shows a wide range of heights; the majority are like the P1 and F1 plants, but approximately 4 of 1000 are only 12 cm high and about 4 of 1000 are 36 cm high. (a) What mode of inheritance is occurring here? (b) How many gene pairs are involved? (c) How much does each gene contribute to plant height? (d) Indicate one possible set of genotypes for the original P1 parents and the F1 plants that could account for these results. (e) Indicate three possible genotypes that could account for F2 plants that are 18 cm high and three that account for F2 plants that are 33 cm high.
A strain of plants has a mean height of 24 cmcm. A second strain of the same species from a different geographical region also has a mean height of 24 cmcm.
When plants from the two strains are crossed together, the F1F1 plants are the same height as the parent plants.
However, the F2F2 generation shows a wide range of heights; the majority are like the P1P1 and F1F1 plants, but approximately 4 of 1000 are only 12 cmcm high, and about 4 of 1000 are 36 cmcm high.
A strain of plants has a mean height of 24 cmcm. A second strain of the same species from a different geographical region also has a mean height of 24 cmcm.
When plants from the two strains are crossed together, the F1F1 plants are the same height as the parent plants.
However, the F2F2 generation shows a wide range of heights; the majority are like the P1P1 and F1F1 plants, but approximately 4 of 1000 are only 12 cmcm high, and about 4 of 1000 are 36 cmcm high.
How many gene pairs are involved?
Express your answer as an integer.
Chapter 21 Solutions
ESSENTIALS OF GENETICS-W/MOD.ACCESS
Ch. 21 -
CASE STUDY | A genetic flip of the coin
On July...Ch. 21 - CASE STUDY|A genetic flip of the coin On July 11,...Ch. 21 -
CASE STUDY|A genetic flip of the coin
On July...Ch. 21 - HOW DO WE KNOW?
1. In this chapter, we focused on...Ch. 21 - Review the Chapter Concepts list on page 422....Ch. 21 -
3. Define the following: (a) polygenic, (b)...Ch. 21 - A dark-red strain and a white strain of wheat are...Ch. 21 - Height in humans depends on the additive action of...Ch. 21 -
6. An inbred strain of plants has a mean height...Ch. 21 - Prob. 7PDQ
Ch. 21 - In the following table, average differences of...Ch. 21 - What kind of heritability estimates (broad sense...Ch. 21 - List as many human traits as you can that are...Ch. 21 - Corn plants from a test plot are measured, and the...Ch. 21 -
12. The following variances were calculated for...Ch. 21 - The mean and variance of plant height of two...Ch. 21 - A hypothetical study investigated the vitamin A...Ch. 21 - In a herd of dairy cows the narrow-sense...Ch. 21 - In an assessment of learning in Drosophila, flies...Ch. 21 - Suppose you want to develop a population of...Ch. 21 -
18. In a population of tomato plants, mean fruit...Ch. 21 - In a population of 100 inbred, genotypically...Ch. 21 - In a cross between a strain of large guinea pigs...Ch. 21 - While most quantitative traits display continuous...
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