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Module 10 Lesson 4 Progress Check

Prompt

Answer the following "Check Your Progress" questions for lesson 4.

3, 5 (p.272)

Response

  1. Interpret: Can two parents with albinism have an unaffected child? Explain.

    No, two parents with albinism cannot have an unaffected child. Albinism is caused by a recessive allele, and since both parents have albinism, they can only pass on the alleles for albinism to their offspring, ensuring that any child they have will also be affected by albinism.

  2. Math Connection: Phenylketonuria (PKU) is a recessive disorder. If both parents are carriers, what is the probability of this couple having a child with PKU? What is the chance of this couple having two children with PKU?

    If both parents are carriers of Phenylketonuria (PKU), each parent has a genotype of Aa, where A is the normal allele and a is the allele for PKU. The probability of them having a child with PKU (aa) is 1 in 4, or 25%, as per Mendelian genetics. The chance of this couple having two children both with PKU is the product of the individual probabilities, which is \( \frac{1}{4} \times \frac{1}{4} = \frac{1}{16} \), or 6.25%.