Download Name: Intro to Genetics Review WS Vocabà Define the following

Name:
Intro to Genetics Review WS
Vocab Define the following terms
Homozygous
Heterozygous
Recessive
Haploid
Genotype
Karyotype
phenotype
Sex chromosomes
Dominant
Autosomes
Questions:
1. Mendelian Genetics
a. Who was Gregor Mendel?
b. What did Mendel do to contribute to the study of genetics?
c. What four conclusions did Mendel come to after conducting his pea plant experiments?
d. **Compare and contrast the law of segregation and the law of independent assortment.
2. **How does the process of meiosis create gametes?
a. **How does an organism guarantee genetic variation with each offspring?
3. What is the purpose of making a karyotype?
4. What are the symbols used in a pedigree?
5. What is the purpose of a pedigree?
6. What is the difference between an autosomal recessive and an autosomal dominant disorder? What are the
genotypes of the people that express a condition in each?
7. How does the environment cause changes in phenotype? Provide an example.
8. What conclusions can be made about how the environment influences phenotype using twin studies?
Karyotype
Based on what you learned in class and on the lab, what observations can you make about the following karyotype?
(What condition is shown here?)
Punnett Square Problems
Identify the following sets of alleles as being homozygous recessive, heterozygous, or homozygous dominant
Hh:
BB:
gg:
Dd:
ww:
YY:
Monohybrid Crosses
 In pea plants, round peas is a dominant trait. What are the genotypes & phenotypes of the offspring produced
when a homozygous dominant round peas are mated with homozygous recessive wrinkled peas?
 In pea plants, round peas is a dominant trait. What are the genotypes and phenotypes of the offspring
produced when two heterozygous pea plants are mated?
 Long whiskers are the dominant trait in harbor seals, whereas short whiskers are recessive. What are the
possible genotypes and phenotypes produced when a heterozygous male is mated with a homozygous recessive
female? What are the ratios for genotype and phenotype? What is the probability that the offspring will have
long whiskers?
Dihybrid Crosses
 Long trunks and long tusks are dominant traits in elephants. What is the ratio of possible phenotypes produced
when a male that is homozygous dominant for trunks/heterozygous for tusks is crossed with a female that is
heterozygous for trunks and homozygous recessive for tusks?
 Chocolate color and blue eyes are recessive traits in Labrador retrievers. You have two dogs. Your male is
homozygous recessive for both chocolate color and blue eyes and your female is heterozygous for both traits.
You would like to breed your male and female labs, and want to know what are the possible phenotypes of the
liter? What is the probability that you’ll have brown haired blue eyed puppies?
Complex Inheritance Patterns Answer each question on a separate sheet of paper and write Punnett squares where
necessary
Incomplete Dominance
a. A cross between a 3-eyed alien and a 1-eyed alien produces offspring that have two eyes
i.
If a homozygous 3-eye crosses with a homozygous 1-eye, what is the percent chance of having a two
eyed offspring?
ii.
If two two-eyed aliens cross, what is the percent chance of having a two eyed offspring?
iii.
If a homozygous 3-eye crosses with a 2-eye, what is the percent chance of having a two eyed offspring?
Codominance
b. A cross between a black cat and a tan cat produce a tabby pattern (black & tan fur together)
i.
What pattern of inheritance does this illustrate?
ii.
What percent of kittens would have tan fur if a tabby cat is crossed with a black cat?
iii.
What percent of kittens would have black fur it a tabby cat is crossed with a black cat?
iv.
What percent of kitten would have a tabby pattern if a black cat is crossed with a tan cat?
Multiple Allele- Blood Type
c. Blood genotyps
i.
If you have type A blood, what are your possible genotypes? ______________________
ii.
If you have type B blood, what are your possible genotypes? ______________________
iii.
If you have type AB blood, what are your possible genotypes? _____________________
iv.
If you have type O blood, what are your possible genotypes? ______________________
d. Could two individuals with type A blood ever produce offspring with Type O? Explain with punnett square.
e. A couple has a child with Type A blood. If one parent is Type O, what are the possible genotypes of the other
parent?
f. Cross a woman with type AB to a man with type AB. Show punnett square, genotypes and phenotypes.
Sex-Linked Traits
g. In fruit flies, the gene for white eyes is sex-linked recessive. (R) is red and (r) is white. Cross a white-eyed female
with a normal red-eyed male.
i.
What percent of the males will have red eyes? White eyes?
ii.
What percent of the females will have red eyes? White eyes?
iii.
What total percent of the offspring will be white-eyed?
iv.
What percent of the offspring will be carriers of the white eye trait?
h. Two normal visioned parents have a color-blind son. Give the genotype of both parents and the son
Pedigree Problems
a. Which best describes the genetics of the afflicting allele in the following pedigree (it is a pedigree of taste
blindness) How do you know?
i.
autosomal dominant
ii.
autosomal recessive
b. On the soap opera “The Young and the Restless”, several individuals suffer from a rapid aging syndrome in which
a young child is sent off to boarding school and returns three months later an angry teenager. Victims have
been known to age up to two decades in variations of the disorder. In the Newman family, siblings Nicholas and
Victoria aged from ages six and eight to sixteen and eighteen within a few months. Their parents, Victor and
Nikki, are not affected; in fact, they never seem to age at all.
i.
What is the mode of inheritance of the rapid aging disorder affecting Nicholas and Victoria?
ii.
How so you know what the mode of inheritance is?
iii.
Draw a pedigree to depict this portion of the Newman family.
c. Achnodroplasia is a common form of hereditary dwarfism that causes very short limbs, stubby hands, and an
enlarged forehead. Below are three pedigrees depicting families with this specific type of dwarfism.
i.
Identify the individuals using Roman numerals for the generation and numbers to identify the
individuals.
ii.
What is the most likely mode of inheritance? (Dominant or Recessive)
iii.
Explain your reasoning.
d. Draw a pedigree to depict the following family:
i.
One couple has a son and a daughter with normal pigmentation. Another couple has one son and two
daughters with normal pigmentation. The daughter from the first couple has three children with the son
of the second couple. Their son and one daughter have albinism; their other daughter has normal
pigmentation.
i.