Name:_______________________________________________________  Date:___________

Bikini Bottom Genetics

Use the information for SpongeBobís traits below to complete the genetics problems.

Trait

Mode of Inheritance

Possible Phenotypes

Body Shape

Sex-linked

Squarepants (XS)

Roundpants (Xs)

 

 

Body Color

Incomplete Dominance

Blue (B)

Green

Yellow (Bí)

Eye Shape

Multiple Alleles

Round (IR)

Oval (IO)

Square (i)

Nose Style

Incomplete Dominance

Long (L)

 Medium

Stubby (Lí)

Hole Size

Codominance

Big holes (B)

Duel holes

Small holes (S)

 

 

Note: Round and oval are codominant. A sponge with an IR allele and an IO allele have one round eye and one oval eye and are referred to a mixed eyed. Square is recessive to both round and oval.

1. One of SpongeBobís cousins, SpongeBillyBob, recently met a cute squarepants gal, SpongeGerty at a local dance and fell in love. SpongeGertyís father is a squarepants and her mother is a roundpants. Use your knowledge of genetics to answer the questions below.

 

a. What is SpongeGertyís fatherís genotype?  ________________    http://topcartooncharacters.com/wp-content/uploads/2015/12/SpongeBob-SquarePants-18.jpg

b. What is SpongeGertyís motherís genotype?  _______________

c. Complete the Punnett square.

 

 

 

        

 

 

Phenotypic Ratio:

 

Genotypic Ratio:

 

d. What is SpongeGertyís genotype? __________________

 

2. SpongeBillyBob is a squarepants shape.

a. What is SpongeBillyBobís genotype? _________________

b. Complete the Punnett square to show the possibilities that would results if SpongeBillyBob and SpongeGerty had children.

 

 

 

 

   

 

 

Phenotypic Ratio:

 

Genotypic Ratio:

 

c. What is the probability (percentage) that they will have a daughter with squarepants? _______

d. What is the probability (percentage) that they will have a daughter with roundpants? _______

e. What is the probability (percentage) that they will have a son with squarepants? ___________

 

3. SpongeBobís mother is so proud of her son and his new wife, SpongeSusie, as they are expecting a little sponge. She is hoping the new arrival will be blue like SpongeSusie and many members of her family.

a. Complete the Punnett square to show the probability that the baby sponge will be blue.

 

 

 

   

 

 

Phenotypic Ratio:

 

Genotypic Ratio:

 

b. What is the probability that the new baby sponge will be blue? ____________

c. What color will the new baby sponge be?  ____________________

 

4. SpongeBobís aunt is famous around town for her itty, bitty stubby nose! She recently met a cute squarepants fellow with a medium nose. Would it be possible for them to have a child with a regular long nose?

a. Complete the Punnett square to show the probability that they can have a child with a long nose.

 

 

 

 

   

 

 

Phenotypic Ratio:

 

Genotypic Ratio:

 

b. What is the probability (percentage) that they will have a child with a long nose? _______

c. What is the probability (percentage) that they will have a child with a medium nose? _______

d. What is the probability (percentage) that they will have a child with an itty, bitty stubby nose? ___________

 

5. SpongeBobís aunt, SpongeWilma, has the biggest round eyes in the family. Wilma is believed to be heterozygous for her round eye shape. SpongeBobís uncle, SpongeWilbur, has oval eyes and he is heterozygous as well.

a. Complete the Punnett square to show the possibilities that would result if SpongeWilma and SpongeWilbur had children.

 

 

 

 

   

 

 

Phenotypic Ratio:

 

Genotypic Ratio:

 

b. What is the probability (percentage) that they will have a child with round eyes? _______

c. What is the probability (percentage) that they will have a child with oval eyes? __________

d. What is the probability (percentage) that they will have a child with square eyes? _________

e. What is the probability (percentage) that they will have a child with mixed eyes? _________

 

6. SpongeBobís sister, SpongeBetty, only big holes and SpongeBobís brother, SpongeBurt, only has small holes. SpongeBob has duel holes (both big and small holes).

a. Complete the Punnett square to show the genotypes of SpongeBobís parents.

 

 

 

 

   

 

 

Phenotypic Ratio:

 

Genotypic Ratio:

 

b. What is SpongeBobís momís genotype? __________________

c. What is SpongeBobís momís phenotype? _________________

d. What is SpongeBobís dadís genotype? __________________

e. What is SpongeBobís dadís phenotype? _________________

 

7. Roundpants is a recessive sex-linked trait. Label the following pedigree for SpongeBobís family.