Download Genetics Practice Sheet

Genetics Practice Sheet
____points!!
Section A (__ Points)
Identify whether the allele is dominant (D) or recessive (R).
1. B ______
4. A ______
2. b ______
5. f ______
3. W ______
6. m ______
Section B (__ Points)
Identify whether the gene pair will display as dominant (D) or recessive (R).
1. BB ______
4. Gg ______
7. Aa ______
2. aa ______
5. FF ______
8. DD ______
3. Ww ______
6. pp ______
Section C (__ Points)
Identify whether the genotype is homozygous (Ho) or heterozygous (He).
1. HH ______
4. yy ______
7. JJ ______
2. GG ______
5. Ff ______
8. Pp ______
3. Bb ______
6. mm ______
Section D (__ Points)
Identify whether the genotype is homozygous dominant (HomD), heterozygous (He), or
homozygous recessive (HomR).
1. KK __________
5. JJ __________
9. DD __________
2. ll __________
6. Hh __________
10. Ww __________
3. dd __________
7. cc __________
4. Tt __________
8. RR __________
Section E (__Points)
Identify the phenotype.
1. Brown eyes are dominant to green eyes. Fill in the blanks with “brown” or “green” eyes.
BB _______________ Bb _______________ bb ______________
2. A full head of hair is dominant to baldness. Fill in the blanks with “hair” or “bald”.
Hh _______________ hh _________________
HH _______________
3. Curly hair is dominant to straight hair. Fill in the blanks with “curly” or “straight”.
cc ________________ CC _________________
Cc ________________
4. Tongue rolling is a dominant trait, so rollers are dominant and nonrollers are recessive
Fill in the blanks with “roller” or “nonroller”.
TT ________________ tt ___________________ Tt ________________
Section F (__ Points)
1. This Punnett Square shows a father and mother that are both heterozygous for tongue
rolling. Tongue rolling is a dominant trait. The possible genotypes for their children are
shown.
2. Color the heterozygous offspring yellow, homozygous recessive offspring red and the
homozygous dominant offspring purple.
a. How many offspring have heterozygous genotypes?
____ out of ______
OR ________%
b. How many offspring have homozygous genotypes?
____ out of ______
OR ________%
c. How many offspring have homozygous recessive genotypes?
____ out of ______
OR ________%
d. What is the probability of a heterozygous child?
__________%
e. What’s the probability that their child will be able to roll his tongue?
__________%
Section G (__ Points)
1. Felicia and Christian want to know if their child will have curly (H) or straight (h) hair. The
mom has curly hair and the dad has straight hair. Fill in the Punnett square to see what type of
hair their child may have.
H
h
h
h
a. Is Felicia’s genotype on the left or top? ______________
b. Is Felicia’s genotype homozygous or heterozygous?
__________________
c. Explain why Felicia’s hair is curly. _________________________
_________________________________________________
_________________________________________________
d. Use a colored pencil to lightly shade in the boxes that are heterozygous.
e. What is the probability that Felicia and Christian’s child will have curly hair?______%
f. What is the probability that their child will have straight hair? ______%
BONUS
2. The same couple wants to know what color hair their child will have. Felicia has brown hair
(B) but her father had red hair (b). Christian has red hair (b) and both his parents had red hair
too. Fill in a Punnett square to see what color hair their child may have.
a.
b.
c.
What percentage of their children will have brown hair?
__________%
What percentage of their children will have red hair?
__________%
Explain how a child can have red hair when both parents have brown
hair.____________________________________________
_______________________________________________
_______________________________________________