1) A representative sample of lamb weaning weights is shown below, expressed
in pounds. Determine the weight limits within which 95% of all lambs
from this population are expected to wean. 81, 81,
83, 101, 86, 65, 68,
77, 66, 92, 94, 85,
105, 60, 90.
Answer: 55.7 lb. > wt > 108.9 lb.
2) Consider the following data on yield in inbred lines of tomatoes (bushels
The R26 x R93 hybrids were randomly crossbred to produce an F2
generation. The F2 yielded
253 bushels of tomatoes per acre, with a standard deviation of 97. What is the broad-sense
heritability of this trait?
Answer: H2 = 72.7%
3) One of the major genes encoding coat color in domestic cats is X-linked. CBCB and CBY cats are black, COCO and COY cats are orange, and CBCO cats are "tortoise-shell." A survey of Nashville cats found 218 black male, 151 black female, 37 orange male, 6 orange female, and 93 tortoise-shell females. What is the frequency of the CB gene?
4) Attached ear lobes and widow's peak are two independently assorting
human traits apparently encoded by recessive alleles. A sample of
100 people yielded the following: 6 with both traits, 24 with attached lobes
only, and 13 with widow's peak only. Assuming Hardy-Weinberg
equilibrium, what are the frequencies of the attached and widow's peak genes?
widow's peak = 0.436
attached = 0.548
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