Download Name: :____________Pd:____ Genetics Review For Quiz #1

Name:___________________________________________Date:____________Pd:____
Genetics Review
For Quiz #1
(Mendel, Incomplete and Co-dominance, Polygenic, Multiple Alleles)
1. Why were pea plants easy for Mendel to work with?
2. Define genotype.
3. What do the two letters in a genotype stand for?
4. Where does each allele come from?
5. Define phenotype.
6. If tongue rolling is dominant (R) over non-rolling (r), an example of a homozygous
genotype is _________. An example of a heterozygous genotype is _______.
7. How is codominance different from incomplete dominance?
8. How does the environment affect the expression of a trait?
9. Give an example of the environment influencing a trait.
10. When there are more than two alleles for a gene it is called ____________
____________.
When there is more than one gene controlling a trait it is called ___________________
______________________.
11. In pea plants, tall (T) is dominant to dwarf (t). Show the cross between a heterozygous
tall and a dwarf plant. What is the genotypic and phenotypic ratio for the offspring?
Genotypic Ratio (use percents): ____________________________________
Phenotypic Ratio (use percents): ___________________________________
12. Show the cross between two heterozygous tall plants. What is the genotypic and
phenotypic ratio of the offspring?
Genotypic Ratio (use percents): ____________________________________
Phenotypic Ratio (use percents): ___________________________________
13. Tiger Syndrome is an autosomal dominant disease that causes lower body paralysis.
Jack’s father has Tiger Syndrome, but his brother and mother do not. What is the
probability that Jack will have Tiger Syndrome like his father?
________% chance for Jack
14. Blarney’s disease is an autosomal recessive disease that causes blindness no later than
age five. Anup and Sienna, neither of whom is blind, have a child who develops
Blarney’s disease. What are Anup’s and Sienna’s genotypes?
_____________ X _____________ (parents’ genotypes)
15. SpongeBob loves growing flowers for his pal Sandy. Her favorite flowers, Poofkins, are
found in red, blue and purple.
a. Is Poofkin color an example of codominance or incomplete dominance?
b. If SpongeBob crossed a Poofkin with red flowers with a Poofkin with blue
flowers, how many of the plants would have red flowers?
_________% red flowers
c. How many of the plants would have purple flowers? ______________%
d. How many of the plants would have blue flowers? ___________%
16. Sandy would really love to have a bouquet of red, blue and purple flowers. What are
the genotypes and phenotypes of the two flowers SpongeBob would have to cross to
make her happy? You may use the Punnett Square below.
__________x________ (parent genotypes)
__________x_________(parent phenotypes)
17. If Poofkin color was a trait that followed the principle of codominance, what would be
the three possible phenotypes for Poofkin flowers?
1. __________________________
2. __________________________
3. __________________________
18. In Bikini Bottom, jellyfish color is codominant; jellyfish are either blue, yellow, or blue
with yellow spots. If blue jellyfish were crossed with yellow jellyfish, and 100 jellyfish
were produced from this cross, how many would you expect for each phenotype?
Yellow - _______
Blue- _______
Blue with yellow spots- _______
19. What is the probability that a couple whose blood types are AB and O will have a child
with blood type A?
_____________% chance of Type A
20. Human blood type is an example of Mendelian dominance and __________-dominance.
21. A woman with blood type B whose father was blood type O marries a man with blood
type O. What will be the possible genotypes and phenotypes of their children?
Genotypes: __________________________
Phenotypes:_________________________
22. Oh no! You are a new nurse in the delivery room of the Princeton-Plainsboro Hospital
and you are so tired that you mixed up the wristbands that identify two babies that were
just born. Mr. and Mrs. Capaferi have blood types O and AB, and Mr. and Mrs. Vidalia
have blood types B and A. You determine that Baby #1 has blood type O and Baby #2
has blood type A. Who belongs to whom?
Baby #1: ________________
Baby #2: _________________
23. List three human traits that are the result of polygenic inheritance:
1. _____________________________________________
2. _____________________________________________
3. _____________________________________________
24. Assume that height in a plant is controlled by two genes, and that each dominant allele
contributes 5 cm to a base height of 20 cm (ie: aabb = 20 cm; Aabb=25 cm, etc)
a. What is the height of a plant with the genotype AABB?
b. What is the genotype of a plant that is 35 cm tall?