Echinoderms Are Unique in Their

question 42

Multiple Choice

Echinoderms are unique in their:

• A)five-fold symmetry.
• B)skeletons made of interlocking plates of protein.
• C)water vascular system.
• D)skeletons made of interlocking plates of calcite.
• E)filter feeding.

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Definitions:

Experimental Group

A group of subjects in an experiment who are exposed to the variable under investigation to study its effect.

Independent Variable

The variable in an experiment that is manipulated or changed by the researcher to determine its effect on the dependent variable.

Placebo

A substance with no therapeutic effect, often used as a control in testing new drugs.

Control Group

In an experiment, a group of subjects that does not receive the treatment being tested and is used as a benchmark to measure how the other tested subjects do.