In a Comparison of Birds and Mammals, Having Four Limbs

question 72

Multiple Choice

In a comparison of birds and mammals, having four limbs is ________.

• A) a shared ancestral character
• B) a shared derived character
• C) a character useful for distinguishing birds from mammals
• D) an example of analogy rather than homology

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Definitions:

Radon-222

A naturally occurring radioactive gas produced by the decay of uranium in the Earth's crust, known for its health risks, particularly lung cancer, when accumulated in buildings.

Air Pollutant

Substances in the air that can have harmful effects on the health of living creatures or the environment, including gases, particulates, and biological molecules.

Global Warming

The ongoing rise in Earth’s surface temperature, primarily due to the emission of greenhouse gases from human activities, leading to climate change and associated impacts.

Stratosphere

The layer of the Earth's atmosphere located above the troposphere, characterized by a slight temperature increase with altitude and the presence of the ozone layer.