Why Don't Recessive Alleles That Cause Severe Disorders Disappear from Human

question 143

Multiple Choice

Why don't recessive alleles that cause severe disorders disappear from human populations?

• A) new alleles can arise by mutation.
• B) in heterozygotes, the dominant allele suppresses the recessive one but does not eliminate its presence.
• C) in heterozygotes, although the trait associated with the recessive allele is not demonstrated, the allele may be passed on to offspring.
• D) some recessive traits are not lethal nor do they interfere with reproduction.
• E) all of these.

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Definitions:

Categorical

Pertaining to data that can be divided into specific groups or categories that are mutually exclusive.

Data

Collected information or facts, typically numerical, that are used as a basis for reasoning, discussion, or calculation.

Categorical Variable

A type of variable that can take on one of a limited, and usually fixed, number of possible values, assigning each individual or other unit of observation to a particular group or nominal category.

Social Security Number

A unique nine-digit number assigned to U.S. citizens, permanent residents, and temporary working residents that is used for tracking individuals for social security and taxation purposes.