When a Scientist Describes the "Body Plan" of a Phylum

question 38

Multiple Choice

When a scientist describes the "body plan" of a phylum, he or she is implying that ________.

• A) organisms direct their own evolution in order to maximize their success
• B) animals evolve according to a pre-ordained plan
• C) the body shapes we see now have been more successful than others in the past
• D) mutations have arisen that allow only some shapes to be produced

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Definitions:

Compound

A substance made up of two or more elements chemically combined in fixed proportions.

Sodium Chloride

A chemical compound known as table salt, composed of sodium and chlorine atoms, essential for human health but required in moderation.

Molecule

The smallest unit of a chemical compound that can exist, consisting of two or more atoms bonded together.

Compound

A substance formed by the chemical combination of two or more elements in fixed proportions.