Autumn Examinations 2007 / 2008
Exam Code(s) 3BS, 3MR
Exam(s) Third Undenominated Science, Third Marine Science
Module Code(s) Z0313
Module(s) Evolutionary Developmental Zoology
Paper No. I
External Examiner(s) Professor C. Holland
Internal Examiner(s) Professor W. Arthur
*Dr. G. McCormack
Dr. U. Frank
Instructions:
Answer 4 questions
Duration 3 hrs
No. of Pages 2
Department(s) Zoology
1. Answer both parts
A) In an electrophoretic study of enzyme variation in a species of grasshopper, you find 62
A1A1, 49 A1A2 and 9 A2A2 individuals in a sample of 120. Show that p=0.72 and q=0.28, and
that the genotype frequencies of A1A1, A1A2 and A2A2 are approximately 0.51, 0.41 and 0.08
respectively. Demonstrate that the genotype frequencies are in Hardy-Weinberg equilibrium.
B) List the assumptions of the Hardy-Weinberg Law and briefly describe how they are often
violated in nature.
Table of Chi-squared values, d.f. = degrees of freedom.
Probability of a larger value of 2
d.f.
0.10
0.05
0.01
0.001
1
2.7
3.8
6.6
10.8
2 4.6 6.0 9.2 13.8
3
6.3
7.8
11.3
16.3
4 7.8 9.5 13.3 18.5
5
9.2
11.1
15.1
20.5
6 10.6 12.6 16.8 22.4
8 13.4 14.1 20.1 26.1
10
16.0
18.3
23.2
29.6
12 18.5 21.0 26.2 . 32.9
20
28.4
31.4
37.6
45.3
25 34.4 37.7 44.3 52.6
