Practice Quiz for General Genetics
Chapter 3-- Probability and Statistics

Answers are at the bottom of the page. It would be best to answer all the questions before looking at the answers rather than simply memorizing the answers to these questions.

1. To determine the probability of having first a boy, then a girl, and finally a boy, we would use the
A. sum rule
B. binomial theorem
C. product rule
D. segregation rule

2. To determine the probability of drawing either a heart or a club from a deck of cards, we would use
A. sum rule
B. binomial theorem
C. product rule
D. segregation rule

3. If two people who are both heterozygous for Huntington's disease (an autosomal dominant trait) marry, what is the probability that they will have three children, all of which are normal?
A. 0.140
B. 0.422
C. 0.250
D. 0.016

4. If a person who is heterozygous for polydactyly (an autosomal dominant trait) marries a person who is heterozygous for polydactyly, what is the probability that they will have four normal children and two children with extra fingers or toes?
A. 0.2966
B. 0.0330
C. 0.0198
D. 0.0022

5. In doing a chi-square test on the results of a trihybrid cross, the number of degrees of freedom would be
A. 8
B. 7
C. 4
D. 3
E. 1

6. In hypothesis testing, the most common level of significance (alpha) that is used by statisticians is
A. 0.95
B. 0.50
C. 0.10
D. 0.05

7. Given a normal human with 46 chromosomes, what is the probability that during gamete formation all of the paternal gametes will wind up in the same gamete
A. 1/2
B. (1/2)^23
C. (23/2)
D. 23^0.5

8. The statistical test that is used to compare an observed distribution to an expected distribution is
A. a t-test
B. analysis of variance
C. means
D. chi-square test

9. Given a cross between a plant that is heterozygous purple-flowered and a plant that is homozygous white-flowered, what is the probability of obtaining 4 purple flowers and 7 white flowers among the offspring?
A. 0.5000
B. 0.1611
C. 0.8389
D. 0.0005

10. In doing a chi-square test on the results of a dihybrid cross, the critical value to reject the null hypothesis is (the chi-square chart is in your textbook)
A. 7.815
B. 11.345
C. 3.841
D. 14.067
E. 2.366


1.C; 2.A; 3.D; 4.B; 5.B; 6.D; 7.B; 8.D; 9.B; 10.A
Provide comments to Dwight Moore at dmoore@emporia.edu.
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