Echinoderms

question 23

Multiple Choice

Echinoderms

• A)are clearly related to cnidarians because of their radial symmetry.
• B)may have evolved from a sessile ancestor.
• C)probably evolved from pterobranch hemichordates.
• D)do not show relationships to any other group of animals.

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Definitions:

Mowrer's Two-Factor Theory

Mowrer's Two-Factor Theory is a psychological theory that integrates classical conditioning and operant conditioning to explain the development of phobias and anxiety.

Avoidance

A behavioral response aimed to prevent an unpleasant outcome or stimulus, often developed as a coping mechanism in both humans and animals.

Feared Stimulus

A specific object, situation, or activity that elicits a strong fear response due to conditioning or traumatic experiences.