Name:_________________________ Partner:_________________________

Gene-o-mania is the ultimate genetics challenge. Your mission, working by yourself, or with a partner is to complete this packet. If at any point I catch you mindlessly copying answers from one of your classmates, you and the person you’re copying from will both receive 0’s on this packet.

Part A Vocabulary: (24pts)

1. Genetically inherited features of an organism are called ______________.

2. The sequence of DNA that determines each specific features is called a ____________.

3. Different varieties of the same gene are called ___________.

4. Genes are carried on _____________________.

5. A somatic cell that contains two copies of each chromosome is called ________________.

6. Corresponding chromosomes are called _____________________.

7. Each chromatid carries _______ copy/copies of each gene.

8. Due to the presence of two chromatids per chromosome, each cell contains __________ copies of each gene.

9. Chromosomes not related to determining the sex of an organism are know as ___________ chromosomes

10. All cells that are non-sex cells are categorized as ________________ cells.

11. ________________ is the process of cell division that produces ________________.

12. At the conclusion of meiosis, each gamete cell carries __________ copy of each chromosome and is called _______.

13. The genetic makeup of an individual is called their __________.

14. The physical appearance of an individual is called their ___________.

15. When two different alleles are present in an individual’s genotype the individual is said to be __________________________.

16. The allele that is expressed in an individual with two different alleles is said to be __________________________.

17. The allele that is covered up in an individual with two different alleles is said to be____________________________.

18. _______________ is a term that refers to the genotype of an individual that has two copies of the dominant allele.

19. ______________ is a term that refers to the genotype of an individual that has two copies of the recessive allele.

20. The dominant allele is abbreviated with a ______________ letter.

21. The recessive allele is abbreviated with a ______________ letter.

22. What is the genotype of a homozygous dominant individual for trait A? ______________

23. What is the genotype of a heterozygous individual for trait A? ______________

24. What is the genotype of a homozygous recessive individual for trait A? ______________

Part B: Basic Punnet Square Problems (8pts per problem, 24pts total) :

Problem A: In guinea pigs, black coat color is dominant to brown coat color and is carried on an autosomal chromosome. Use letter “B” to represent coat color.

“B” represents what phenotype?
“b” represents what phenotype?
Identify the genotype of each parent and show the expected offspring from each cross…
1. Black Heterozygous Male x Brown Homozygous Recessive Female ( _____ x _____ )
2. Black Heterozygous Male x Black Homozygous Dominant Female ( _____ x _____ )
3. Brown Homozygous recessive male x Black Homozygous Dominant Female ( _____ x _____ )

A. B. C.

Problem B: Below is a chart showing three phenotypic crosses of cucumber plants the phenotypes of their offspring. Use all of the information to complete a punnett square for each cross. Use “G” for the dominant trait (green) and “g” for the recessive trait (striped). This trait is carried on an autosomal chromosome.

Phenotype of Cucumbers Crossed	Phenotype of Offspring
a. Green x Striped	All Green
b. Striped x Striped	All Striped
c. Green x Green	Some Green & Some Striped

A. B. C.

Genotypic Ratio: __________ Genotypic Ratio: __________ Genotypic Ratio:__________

Phenotypic Ratio:__________ Phenotypic Ratio:__________ Phenotypic Ratio:__________

Problem D: Garden squash plants can produce white or yellow fruit. A gardener saved the seeds from yellow and white squash and performed crosses with these seeds. In cross A, two seeds obtained from yellow plants produced both white and yellow offspring. In cross B, two seeds obtained from white squash produced only white offspring. Show how the two crosses mentioned above are possible. Use the letter H to represent the color of trait that is carried on an autosomal chromosome.

How did you identify the recessive trait?

Part C: Penny Lab #1: Predicting Genes 20pts per problem

Using two pennies, follow the listed procedure to predict the outcome of the following genetic parings. For this lab, we are concerned about the phenotype of coat color on mice. There are two alleles for the autosomal trait of coat color; B = black coat, b = white coat.

Part A: Calculating Expected Results

Assume that a female mouse has several litters of young in one year. She is heterozygous (Bb) for coat color and mates with a male that is also heterozygous (Bb) for coat color. Complete a Punnett square to calculate the probability of different genotypes for potential offspring. Using the genotypic ratios from your punnett square, calculate how many mice you’d expect to be born (for each genotype) based on 40 mice youngsters. Complete row 5 of the table below. Get 2 coins. One will represent the male mouse, and the other the female mouse. Designate each side of the coin to an allele based on the genotype of the parent.

Male Heads = _____ (B or b)
Male Tails = _____ (B or b)
Female Heads = _____ (B or b)
Female Tails = _____ (B or b)

Table 1: Results of Coin Tosses from part A

Genotype of Offspring	BB	Bb	bb
Phenotype (Coat Color)
Results from Step 4 (Record with Tally Marks)
Total Observed (Sum of Tally Marks)
Expected Results (from 40 tosses)
Difference (Total Obs. – Expected)

Part B: Predicting Mouse Offspring

Suppose you mate a female mouse that is heterozygous (Bb) with a male that is homozygous recessive (bb). Complete a Punnett square to calculate the probability of different genotypes for potential offspring. Using the genotypic ratios from your punnett square, calculate how many mice you’d expect to be born, of each genotype, based on 40 mice youngsters. Complete row 5 of the table below. Get 2 coins. One will represent the male mouse, and the other the female mouse. Designate each side of the coin to an allele based on the genotype of the parent.

Male Heads = _____ (B or b)
Male Tails = _____ (B or b)
Female Heads = _____ (B or b)
Female Tails = _____ (B or b)

Genotype of Offspring	BB	Bb	bb
Phenotype (Coat Color)
Results from Step 4 (Records with Tally Marks)
Total Observed (Sum of Tally Marks)
Expected Results (from 40 tosses)
Difference (Total Obs. – Expected)

Part D: Analysis Questions 20pts:

If you toss a coin, how often do you expect it to land on heads? ____%
If you toss a coin, how often do you expect it to land on tails? ____%
When 2 coins are tossed, what percent of the time do you expect to get the following combinations?
Use a punnett square to prove your answer.
1. Heads/Heads: _____%
2. Heads/Tails: _____%
3. Tails/Tails: _____%
How close were your experimental results to what you expected to get in each of the two tables?

How would you get the observed results to be closer to the expected results? WHY? EXPLAIN! Compare to your results._______________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________
If two mice have 71 black baby mice and 26 white baby mice, what would be the genotypes of the parents? _____ x _____
If two mice have 42 black baby mice and 48 white baby mice, what would be the genotypes of the parents? _____ x _____
A white mouse mates with a black mouse. All 2,387,652 of their babies are black. What is the genotype of the black mouse? _____

Part E: Advanced Punnet Square Problems 15pts per problem

In a dihybrid cross, the inheritance of one trait does not affect the inheritance of alleles for another trait. In the Punnett square, set up a cross between two pea plants. One is heterozygous for both round seeds and green pods. The other has round seeds and green pods and comes from a self pollinated corn plant that has NEVER produced wrinkled seeds or yellow pods. R = round seeds, r = wrinkled seeds, G = green pods, & g = yellow pods.
1. A plant heterozygous for round seeds and green pods has what genotype? (This will also be the genotype for the first parent). _________________
2. What is the genotype of the second parent? ____________
3. If a plant had a phenotype of wrinkled seeds and yellow pods what would be the genotype? ________________.

Identify the genotypic ratio for the offspring of this cross.
Identify the phenotypic ratio for the offspring of this cross.

Two mythical animals called Geewizbos were recently described by their discoverer. One kind of Geewizbo has a wavy body and six tiny feet on it’s underside. It is heterozygous for both traits! The other has a non-wavy body and no feet.
1. The dominant phenotypes are __________________ & __________________.
2. How did you know this?
3. The non-wavy, footless parent had ( dominant / recessive ) alleles.
4. What are the genotypes of two parents?

Figure out the possible genotypes of the F₁ offspring from these parents.

f. In the boxes below, draw one representative of each F₁ phenotype. Write each Geewizbo’s genotype below it.

What is the genotypic ratio for the offspring of this cross? (Example - 1 WwLl)

Part F: Sex Linked Traits Lab (24pts)

Problem: How are Traits on Sex Chromosomes Inherited?

Background: Hemophilia (bleeder’s disease) & red-green colorblindness are due to sex-linked recessive genes. For hemophilia, normal blood clotting X^H is dominant to hemophilia X^h. For red-green colorblindness, X^B represents the gene for normal color vision and X^b represents the gene for color blindness.

Task 1: Identify the genotype of the following individuals?

a) homozygous non-hemophilic woman = ____

b) non-hemophilic man = ____

c) heterozygous non-hemophilic woman =____

d) hemophilic man = ____

e) hemophilic woman = ____

f) homozygous normal vision female = ____

g) colorblind male = ____

h) carrier female = ____

i) normal vision male = ____

j) colorblind female = ___

Task 2: Take two pennies & assign an allele to each side based on the parent’s genotypes for each situation below. Toss each pair of pennies 20times. Record your results in the tables below. Note: Grey areas are calculated based on the probabilities obtained from the Punnett squares. Base your estimate on 40 expected offspring.

Situation 1: Offspring of X^HX^h mother and father X^HY

	# of male offspring		# of female offspring
	Expected (out of 20)	Observed	Expected (out of 20)	Observed
Normal clotting
Hemophilia

Text Box: Coin 1 (Female):
Heads = ____
Tails =_____
Coin 2 (Male):
Heads = ____
Tails = ____

Situation 2: Offspring of X^HX^h mother and father X^hY

Hemophilia

Text Box: Coin 1 (Female):
Heads = ____
Tails =_____
Coin 2 (Male):
Heads = ____
Tails = ____

Analysis Questions: (20pts)

1. How do your results from the lab compare to the expected outcomes?

2. Why is there a difference in the number of genes for blood clotting and color blindness in males and females?

3. In Situation 3, why are there no color-blind children even though one of the parents is color blind?

4. Which of the parent(s) gives the trait of hemophilia to their son?_____________________________

5. Which of the parent(s) gives the trait of hemophilia to their daughter?_________________________

6. A normal man marries a normal woman known to carry the hemophilia gene (a carrier).

For male offspring what % will have hemophilia?
For female offspring what % will have hemophilia?

7. A hemophiliac man marries a normal woman whose father was a hemophiliac.

For male offspring what % will have hemophilia?
For female offspring what % will have hemophilia?