1. Genetics Review

2. What is an allele? Why do we have two alleles for each trait?

3. What is a genotype? Which of the following represent genotypes?XX
XhY
Yellow
Tall RW
Spotted

4. What is a phenotype? Which of the following represent phenotypes?XX
XhY
Yellow
Tall RW
Spotted

5. For each genotype below, indicate whether it is heterozygous (He) or homozygous (Ho).
AA _____
Ee ____
Ii _____
Bb _____
ff ____
Jj _____
Cc _____
Gg ____
kk _____

6. What are the phenotypes for the following genotypes
Purple flowers are dominant to white flowers.
PP __________________
Pp __________________
pp __________________

7. What are the phenotypes for the following genotypes
Round seeds are dominant to wrinkled seeds.
RR __________________
Rr __________________
rr __________________

8. For each phenotype below, list the genotypes (remember to use the letter of the dominant trait)
Straight hair is dominant to curly.
____ straight
____ curly
Pointed heads are dominant to round heads.
_____ pointed
_____ round

9. A TT (tall) plant is crossed with a tt (short plant)
A TT (tall) plant is crossed with a tt (short plant).   What percentage of the offspring will be tall?  ___________

10. A heterozygous round seeded plant (Rr) is crossed with a homozygous round seeded plant (RR).  What percentage of the offspring will be homozygous (RR)?  __________

11. Purple (P) pea flowers are dominant to white (p) pea flowers.
A true-breeding purple pea plant is crossed with a hybrid purple pea plant.
About how many pea plants will be white if 100 plants are crossed?

12. A cross between a blue blahblah bird & a white blahblah bird produces offspring that are silver. The color of blahblah birds is determined by just two alleles. Blue (B) and White (W) This is an example of what type of inheritance?

13. A cross between a blue blahblah bird & a white blahblah bird produces offspring that are silver. The color of blahblah birds is determined by just two alleles.
What are the genotypes of the original blahblah parents?
What is/are the genotypes of the silver offspring?

14. What would the phenotype ratios of offspring produced by two silver blahblah birds ?
___________ % Blue
___________ % White
___________ % Silver

15. Red and white hair color in cows can exhibit codominance
Red and white hair color in cows can exhibit codominance. This means some hairs are red colored and other hairs are white colored. This sometimes gives the look of a mixture, but if individual hairs are analyzed they are only red or white, not pink. When a cow has both red and white hairs its color is referred to as roan. What are the alleles (letter) for a white and red cow? White: ______________ Red ________________

16. If a roan colored cow is crossed with a white cow, what are the possible genotype and phenotype ratios for their offspring?
_____________ % WW
_____________ % RR
_____________ % WR
______________% White
______________ % Red
______________ % Roan

17. Male pattern baldness is a recessive gene located on the X chromosome
Male pattern baldness is a recessive gene located on the X chromosome. If your mother is a carrier and your father does not have baldness (normal), determine your chances of developing male pattern baldness. What kind of inheritance is this? ______________
Write the genotypes of your parents: ______ x ______
________ % of offspring with baldness?
________ % of offspring that don’t have baldness, but are carriers

18. Which of the following are just carriers for a Sex-linked trait
Which of the following are just carriers for a Sex-linked trait? Which of the following are affected by the sex-lined trait? XX
XXc
XcY XY
XcXc

19. In horses, black color depends on a dominant gene (B) and chestnut color is recessive (b). The trotting gait is due to a dominant gene (T) and the pacing gait (t) is recessive. Cross a homozygous black pacer with a chestnut heterozygous trotter.   Parents: _____ X _____

20. Dihybrid Punnett Square X

21. Offspring Genotypes and Probabilities: Offspring Phenotypes and Probabilities:

22. Which shapes are female?
Which shapes are male?
Which shapes are female?
How can you tell which family members have a recessive trait?
Males are square and females are circles

23. Write the genotypes for all individuals --use "A" to represent a dominant allele & "a" to represent a recessive allele.
If there are two different answers for some individuals, then provide both possibilities
Generation #1 --aa, Aa
Generation #2 -- aa, Aa, Aa, aa, Aa, Aa, Aa, aa
Generation #3 --Aa, aa, aa, Aa, Aa, aa

24. What kind inherence was shown in the pedigree?
Autosomal (not sex-linked) Recessive (normal Mendel)
Not sex linked because females had it and their sons did not
Not Autosomal dominant - two parents who do not express the trait have a child who does (not possible with autosomal dominant, since parents would only have recessive allele).