Find expected value for the trait among their offspring | Homework Helpers

3. The mean value of a trait is 250 units and the h2 for the trait is .50. A male and female measuring 240 and 280 units respectively are selected for breeding and they produce several offspring. What is the average expected value for the trait among their offspring?

(a) 250 (b) 255 (c) 260 (d) 265 (e) 270

4. A fish breeder wishes to increase the rate of growth in a fish stock by selecting for increased length at six weeks after hatching. The mean length of 6 week old fingerlings is currently 10 cm. Adult fish that had a mean length of 15 cm at 6 weeks of age were used to produce a new generation of fingerlings. These new fingerlings had a mean length of 12.5 cm. What is the h2 for length at 6 weeks in this population?

(a) .20 (b) .30 (c) .40 (d) .50 (e) .60

Samples of plant height were collected on 4 groups of pine seedlings. The following statistics were calculated for each group:

Group 1 Mean = 15.2 cm Variance = 46 N = 100

Group 2 Mean = 17.0 cm Variance = 10 N = 100

Group 3 Mean = 14.4 cm Variance = 22 N = 100

Group 4 Mean = 15.5 cm Variance = 90 N = 100

5. Which of these groups exhibited the greatest amount of variation?

(a) 1 (b) 2 (c) 3 (d) 4

6. Given the following estimates of various components of genetic variation:

VA = 90 VD = 50 VI = 35 VE = 125

What is heritability in the narrow sense equal to?

(a) .10 (b) .20 (c) .30 (d) .40