Refer to Figure 1

question 9

Multiple Choice

Refer to Figure 1. Federal mobile source air pollution control policies have focused almost exclusively on

• A) emissions per mile.
• B) total quantity of emissions.
• C) number of vehicles.
• D) average miles traveled.

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Definitions:

Recessive Alleles

Genetic variations that must be present in two copies (homozygous) to express a trait, as opposed to dominant alleles that require only one copy.

Epistasis

An interaction between genes where the presence or absence of alleles of one gene influences the expression of another gene.

Alleles

Alleles are alternative forms of a gene that arise by mutation and are found at the same place on a chromosome, contributing to genetic variation in populations.

Locus

A precise, definite location on a chromosome that is the site of a specific gene or genetic marker.