Name____________________________________________ Period ________________Date_______________________
Finding Nemo Genetics
Incomplete Dominance
Marlin and his son, Nemo, live in a sea anemone, which is a beautiful animal related to a
coral reef. The anemones in the ocean where they live are found in three colors: red, blue
and purple. Use the information provided and your knowledge of incomplete dominance to
complete each section below.
1. Write the correct genotype for each color anemone if B represents a blue gene and b
represents a red gene.
Blue - _______________ Red - ________________ Purple - _________________
2. What would happen if a blue anemone were crossed with a red anemone? Complete the
Punnett Square to determine the chances of each anemone color.
(a) Give the possible phenotypes for the offspring
_______________________________
(b) Give the possible genotypes for the offspring
______________________________
(c) How many of the offspring would be red? _________%
(d) How many of the offspring would be blue? _________%
(e) How many of the offspring would be purple? _________%
3. What would happen if two purple anemones were crossed? Complete the Punnett Square
to show the probability of the offspring colors.
(a) Give the possible phenotypes for the offspring
_______________________________
(b) Give the possible genotypes for the offspring
______________________________
(c) How many of the offspring would be red? _________%
(d) How many of the offspring would be blue? _________%
(e) How many of the offspring would be purple? _________%
4. What would happen if a purple anemone were crossed with a blue anemone? Complete
the Punnett Square to show the probability of the offspring colors.
(a) Give the possible phenotypes for the offspring
_____________________________
(b) Give the possible genotypes for the offspring
_____________________________
(C) If 100 offspring were produced from this cross, how many should be expected to
have each of the following colors?
Purple - __________
Blue - _________
Red - __________
Nemo and his friend, Bubbles, love to go to Oyster Field to find pearls. The pearls are
usually white (WW) or pink (ww) but sometimes they find a rare pearl that is gold as a
result of incomplete dominance from oyster crossings. Use this information to help you
complete each section below:
5. What would happen if Nemo and Bubbles crossed two oysters that produce golden
pearls? Complete the Punnett Square to help you determine the probability for each color
pearl.
(a) What percentage of the pearls would be white? ________%
(b) What percentage of the pearls would be pink? _________%
(c) What percentage of the pearls would be gold? __________%
6. What would happen if they crossed a white pearl producing oyster with a gold pearl
producing oyster? Use the Punnett Square to help you determine the probability for each
pearl color.
(a) What percentage of the pearls would be white? ________%
(b) What percentage of the pearls would be pink? _________%
(c) What percentage of the pearls would be gold? __________%
7. What would happen if they crossed an oyster that produces white pearls with an oyster
that produces pink pearls? Use the Punnett Square to help you determine the probability
for each pearl color.
(a) If 100 pearls were produced from this cross, how many
would you expect for each of the following colors?
White - __________ Pink - ___________ Gold - _____________