Which of the Following Is Considered a Variable Gas in Earth's

question 46

Multiple Choice

Which of the following is considered a variable gas in Earth's atmosphere?

• A)water vapor
• B)nitrogen
• C)​oxygen
• D)​argon
• E)​helium

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Definitions:

Temporal Isolation

A mechanism that prevents species from mating because they are active at different times of the day, year, or mating seasons.

Behavioral Isolation

A form of reproductive isolation in which two populations develop differences in mating rituals or behaviors that prevent them from breeding with each other.

Reproductive Isolating Mechanisms

The reproductive barriers that prevent a species from interbreeding with another species; as a result, each species’ gene pool is isolated from those of other species. See prezygotic barrier and postzygotic barrier.

Sympatric Isolating Mechanisms

Sympatric isolating mechanisms are barriers to breeding that occur when two species share the same habitat but develop behaviors or characteristics that prevent them from interbreeding.