Against Which Hard Structure Do the Circular and Longitudinal Muscles

question 36

Multiple Choice

Against which hard structure do the circular and longitudinal muscles of annelids work?

• A) cuticle
• B) shell
• C) endoskeleton
• D) hydrostatic skeleton

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Definitions:

Double-Blind Procedure

is an experimental method in which neither the participants nor the experimenters know who is receiving a particular treatment, to prevent bias in the results.

Subjective World

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Psychoanalytic Methods

Techniques developed by Sigmund Freud and his followers for exploring the unconscious mind, often through free association, dream interpretation, and analysis of transference.

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