​Animals That Have No Internal Backbone, and Whose Skeleton Is

question 24

Multiple Choice

​Animals that have no internal backbone, and whose skeleton is usually located on the exterior of the body rather than the interior, are called:

• A) ​vertebrate.
• B) ​invertebrate.
• C) ​endoskeleton.
• D) ​protist.

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Definitions:

Two Groups

In research, the division of subjects into two distinct categories for comparison, often used in experimental designs to evaluate the effect of treatments.

Two-Tailed Test

A statistical hypothesis test in which the area of interest or rejection region is in both tails of the probability distribution.

One-Tailed Test

A statistical hypothesis test in which the region of rejection is on only one side of the sampling distribution, testing for a direction-specific hypothesis.

Directional Hypothesis

A hypothesis that specifies the direction of the expected difference or relationship between two variables.