GENETICS TEST STUDY GUIDE
VOCABULARY
Phenotype Genotype Gene Heterozygous Homozygous Allele Fertilization Homolog Heredity Haploid Gamete HybridRatioProbability –
Percentage –
Phenotype Ratio –
Phenotype Percentage –
Genotype Ratio –
Genotype Percentage –
Monohybrid –
Incomplete Dominance –
Codominance –
Polygenic Traits –
Pedigree –
Traits –
Inherited Traits –
Acquired Traits –
Diploid –
Sex chromosomes –
QUESTIONS
A complete Punnett square shows
A. only the genotypes of parents and offspring
B. how an offspring's alleles might combine
C. only the dominant alleles in parents and offspring
D. genotypes and phenotypes of parents and offspring
A poodle with black fur (BB) is crossed with a poodle with brown fur (bb). What is the
probability that the offspring will be black?
An organism with the genotype Dd is crossed with an organism with the same genotype.
What is the ratio of offspring displaying the dominant allele to offspring displaying the
recessive allele?
In a plant, tall (D) is the dominant allele. Short (d) is the recessive allele. Which
genotype would a short offspring have?
A. dD
B. dd
C. Dd
D. DD
Each box in a Punnett square shows
A. one possible allele from one parent
B. one possible allele from each parent
C. two possible alleles from one parent
D. two possible alleles from each parent
What is the difference between acquired traits and inherited traits?
What is the difference between incomplete dominance and codominance?
How many total chromosomes do humans have?
In pea plants being tall (T) is dominant to being short (t). What is the genotype ratio and
phenotype ratio for a cross between a heterozygous plant and a short pea plant?
Snapdragon flower color is decided by incomplete dominance. There are two alleles.
Red flowers (R) and White flowers (W). Cross a pink snapdragon with a white
snapdragon.
What percentage of the offspring would have red flowers?
What percentage of the offspring would have white flowers?
What percentage of the offspring would have pink flowers?
In humans blood type is a codominant trait. Cross a woman who is type O with a father
who is type AB.
What percentage of offspring will be type A?
What percentage of offspring will be type B?
What percentage of offspring will be type AB?
What percentage of offspring will be type O?
The hospital is claiming that the child of this couple has type O blood. Is this possible?
Explain.
In humans colorblindness is a sex-linked trait. Having normal vision is the dominant trait
(B). Being colorblind is the recessive trait (b). Cross a colorblind female with a normal
visioned male
What percentage of the offspring would be normal visioned females?
What percentage of the offspring would be colorblind females?
What percentage of the offspring would be colorblind males?
What percentage of the offspring would be normal visioned males?
.
Answer the following questions using the Pedigree below. Huntington’s is NOT a
sex-linked trait.
1
3
4
5
2
6
7
8
11
12
13
14
9
10
15
49. Which members (numbers) of the family above are afflicted with Huntington’s
Disease?
51. How many children did individuals 3 and 4 have?
52. How many boys did 1 and 2 have?
53. How is individual 15 and 5 related?
54. What is the genotype of individual 9?
55. What is the genotype of individual 2?