NAME:
DATE:
BLOCK:
1. For each genotype, indicate whether it is heterozygous (HE) or homozygous (HO)
AA ____
Bb ____
Cc ____
Dd ____
Ee ____
ff ____
GG ____
HH ____
Ii ____
Jj ____
kk ____
Ll ____
Mm ____
nn ____
OO ____
Pp ____
2. For each of the genotypes below, determine the phenotype.
Purple flowers are dominant to white flowers
PP ___________________________
Pp ___________________________
pp ___________________________
Brown eyes are dominant to blue eyes
BB ___________________________
Bb ___________________________
bb ___________________________
Round seeds are dominant to wrinkled
RR ___________________________
Rr ___________________________
rr ___________________________
Bobtails are recessive (long tails dominant)
TT ___________________________
Tt ___________________________
tt ___________________________
3. For each phenotype, list the genotypes. (Remember to use the letter of the dominant trait)
Straight hair is dominant to curly.
____________ straight
____________ straight
____________ curly
Pointed heads are dominant to round heads.
____________ pointed
____________ pointed
____________ round
4. Set up the square for each of the crosses listed below. The trait being studied is round seeds
(dominant) and wrinkled seeds (recessive)
Rr x rr
What percentage of the offspring will be round? _______
NAME:
DATE:
BLOCK:
Rr x R r
What percentage of the offspring will be round? _______
RR x Rr
What percentage of the offspring will be round? ___________
In rabbits, grey hair is dominant to white hair. Also in rabbits, black eyes are dominant to red
eyes.
GG = gray hair
Gg = gray hair
gg = white hair
BB = black eyes
Bb = black eyes
bb = red eyes
5. What are the phenotypes (descriptions) of rabbits that have the following genotypes:
Ggbb ____________________ ggBB ________________________
ggbb ____________________ GgBb _________________________
6. A male rabbit with the genotype GGbb is crossed with a female rabbit with the genotype ggBb
The square is set up below. Fill it out and determine the phenotypes and proportions in the
offspring.
How many out of 16 have grey fur and black eyes? ____
How many out of 16 have grey fur and red eyes? _____
NAME:
DATE:
BLOCK:
How many out of 16 have white fur and black eyes? ____
How many out of 16 have white fur and red eyes? _____
7. A male rabbit with the genotype GgBb is crossed with a female rabbit with the genotype
GgBb The square is set up below. Fill it out and determine the phenotypes and proportions in the
offspring. Draw the Punnet Square.
How many out of 16 have grey fur and black eyes? ____
How many out of 16 have grey fur and red eyes? _____
How many out of 16 have white fur and black eyes? ____
How many out of 16 have white fur and red eyes? _____
Practice with Crosses. Show all work!
8. A TT (tall) plant is crossed with a tt (short plant).
What percentage of the offspring will be tall? ___________
9. A Tt plant is crossed with a Tt plant.
What percentage of the offspring will be short? ______
NAME:
DATE:
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. A homozygous round seeded plant is crossed with a homozygous
wrinkled seeded plant. What are the genotypes of the parents? __________ x _________
What percentage of the offspring will also be homozygous? ______________
12. In pea plants purple flowers are dominant to white flowers.
If two white flowered plants are cross, what percentage of their
offspring will be white flowered? ______________
13. A white flowered plant is crossed with a plant that is
heterozygous for the trait. What percentage of the
offspring will have purple flowers? _____________
BLOCK:
NAME:
DATE:
14. Two plants, both heterozygous for the gene that controls
flower color are crossed. What percentage of their offspring
will have purple flowers? ______________
What percentage will have white flowers? ___________
15. In guinea pigs, the allele for short hair is dominant. (S)
What genotype would a heterozygous short haired guinea pig have? _______
What genotype would a purebreeding short haired guinea pig have? _______
What genotype would a long haired guinea pig have? ________
16. Show the cross for a pure breeding short haired guinea pig
and a long haired guinea pig.
What percentage of the offspring will have short hair? __________
17. Show the cross for two heterozygous guinea pigs.
What percentage of the offspring will have short hair? ________
What percentage of the offspring will have long hair? _______
BLOCK:
NAME:
DATE:
BLOCK:
18. Two short haired guinea pigs are mated several times. Out of 100
offspring, 25 of them have long hair. What are the probable
genotypes of the parents? ________ x ___________ Show the cross to prove it!
Cattle Genetics
Using the information provided, show the punnett square for each of the crosses and answer the
questions. SHOW ALL WORK! YOU MAY USE A SEPARATE SHEET OF PAPER.
Female= XX
Male= XY
Polled = P
Horned = p
Black coat = B
Red coat = b
Solid = S
Spotted = s
Face color white = F
Face color black = f
Solid tail = T
Striped tail = t
Solid legs = L
stocking legs = l
1. A black coated cow is crossed with a red coated bull (Bb X bb). What is the percentage of black
calves? What is the percentage of red calves?
2. A horned cow is crossed with a polled bull (pp X Pp). What is the percentage of horned calves?
What is the percentage of polled calves? Which is more advantageous and why?
3. A solid tailed cow is cross with a solid tailed bull (Tt X Tt). What is the percentage of solid tailed
calves? What is the percentage of striped tailed calves?
4. A cow is crossed with a bull (XX x XY). What is the percentage the calves will be female? What
is the percentage the calves will be male?
5. A solid legged cow is crossed with a solid legged bull (Ll X Ll). What is the percentage the
calves will solid legged? What is the percentage the calves will be stripped legged?
6. A black coated cow is crossed with a black coated bull. (Bb X Bb). What is the percentage of
black calves? What is the percentage of red calves?
7. A solid legged cow is crossed with a stocking legged bull (LL X ll). What is the percentage of
stocking legged calves? What is the percentage of solid legged calves?