Name ______

Incomplete Dominance

SpongeBob loves growing flowers for his pal Sandy! Her favorite flowers, Poofkins, are found in red,blue, and purple. Use the information provided and your knowledge of incomplete dominance tocomplete each section below.

  1. Write the correct genotype for each color if R represents a red gene and B represents a blue gene.

Red - _____ Blue - ______Purple - _____

  1. What would happen if SpongeBob crossed a Poofkin with red flowers with a Poofkin with blue flowers.Complete the Punnett square to determine the chances of each flower color.

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  1. Give the genotypes and phenotypes for the offspring.
  1. How many of the plants would have red flowers? _____%
  1. How many of the plants would have purple flowers? _____ %
  1. How many of the plants would have blue flowers? _____ %

  1. What would happen if SpongeBob crossed two Poofkins with purple flowers? Complete the Punnettsquare to show the probability for each flower color.

/
  1. Give the genotypes and phenotypes for the offspring.
  1. How many of the plants would have red flowers? _____%
  1. How many of the plants would have purple flowers? _____ %
  1. How many of the plants would have blue flowers? _____ %

  1. What would happen if SpongeBob crossed a Poofkin with purple flowers with a Poofkin with blueflowers? Complete the Punnett square to show the probability for plants with each flower color.

/
  1. Give the genotypes and phenotypes for the offspring.
  1. If SpongeBob planted 100 seeds from this cross, how many should he expect to have of each color?
Purple flowers - ______Blue flowers - ______Red flowers - ______

Codominance

SpongeBob and his pal Patrick love to go jellyfishing at Jellyfish Fields! The fields are home to a

special type of blue & yellow spotted jellyfish known as Goobers and only really great jellyfishermen are lucky enoughto catch some on every trip. Many of the jellyfish are yellow (YY) or blue (BB), but some end up with yellow and blue spots as a result of codominance. Use this information to help you complete each section below.

  1. What would happen if SpongeBob and Patrick crossed two “goobers” or spotted jellyfish? Complete thePunnett square to help you determine the probability for each color of jellyfish.

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  1. Give the possible genotypes and phenotypes for the offspring.
  1. What percentage of the offspring would be yellow? _____%
  1. What percentage would be blue? _____ %
  1. What percentage would be “goobers” (spotted)? _____ %

  1. What would happen if they crossed a yellow jellyfish with a goober? Complete the Punnett square to helpyou determine the probability for each color of jellyfish.

/
  1. Give the possible genotypes and phenotypes for the offspring.
  1. What percentage of the offspring would be yellow? _____%
  1. What percentage would be blue? _____ %
  1. What percentage would be “goobers” (spotted)? _____ %

An example of a three-allele gene is the ABO blood types of humans. In this case BOTH the (A) and B gene are codominant. The recessive gene O is only seen in the phenotype (Type O) or in heterozygous A or B genotypes.

I is dominant over i, but A & B are codominant.

A : Allele for Type A blood

B : Allele for Type B blood

O: Allele for Type O blood

If you have Type A blood, you are either IAIA or IAi

If you have Type B blood, you are either IBIB or IBi

If you have Type O blood, you are ii(only choice!)

If you have TypeAB blood, you are IAIB(only choice)

Using this information, answer the following question:

  1. Kathy and Jim are heterozygous for their blood type. They have type A blood. Their daughter Julia has type O blood.
  2. What blood type alleles do both Kathy and Jim have?
  1. Their son Ian has never had his blood typed. What are the possible blood type alleles he might have?