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Read again the introductory story for Chapter 3, "The Genetics of Blond Hair in the South Pacific." Based on the information provided in this story, draw a pedigree of a typical Solomon Islander family in which blond hair occurs. Be sure to incorporate the mode of inheritance for blond hair in Pacific Islanders and correct symbols for a pedigree.

a) Autosomal dominant
b) X-linked recessive
c) Autosomal recessive
d) Y-linked dominant

User Greenleaf
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Final answer:

The inheritance of blond hair in the Solomon Islands is autosomal recessive. In a pedigree, fully shaded symbols represent individuals with blond hair, unshaded symbols are individuals without the trait, and dotted symbols are carriers.

Step-by-step explanation:

Drawing a Pedigree for Blond Hair in Solomon Islanders

The inheritance pattern of blond hair in Pacific Islanders, such as those from the Solomon Islands, has been discovered to be autosomal recessive. This means that two copies of the recessive allele are needed for an individual to display the trait. In a pedigree, individuals with the phenotype are shaded, while those without are unshaded. Males are represented by squares and females by circles. Carriers of the allele who do not express the phenotype have a dot inside their symbol.

When creating a pedigree for this family, remember that both parents of a child with blond hair must at least carry one copy of the blond hair allele (since it is a recessive trait). If both parents have dark hair but carry the recessive allele, they will be represented with a dot inside their symbol. Any child with blond hair will be fully shaded. Children with dark hair could either be shaded with a dot if they are carriers or not shaded at all if they have two dominant alleles.

Using this information, a typical Solomon Islander family pedigree with the occurrence of blond hair would show a mix of shaded, unshaded, and dotted individuals, depending on their genotype and whether they have inherited the blond hair allele.

User Shawyeok
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