A Phenotypically Normal Man Has Phenotypically Normal Parents but He

question 20

Multiple Choice

A phenotypically normal man has phenotypically normal parents but he has a sister who has cystic fibrosis caused by a recessive mutant allele. What is the probability that the man is heterozygous for the cystic fibrosis allele?

• A) 1/4
• B) 1/2
• C) 3/4
• D) 2/3
• E) 1/3

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Definitions:

Class Support

The assistance provided by members of a particular social class to one another, which can manifest in various forms including economic help, political solidarity, or social backup.

Distribution System

A network through which a company supplies its products or services to its customers.

Ruling Class

The social class that holds the majority of wealth, power, and influence within a society, often making and enforcing policies and decisions.

Elite Groups

A small, select group of people within society who hold a disproportionate amount of wealth, privilege, political power, or skill.