A Sea Urchin Is a Member of the Phylum

question 90

Multiple Choice

A sea urchin is a member of the phylum

• A) Echinodermata.
• B) Mollusca.
• C) Annelida.
• D) Platyhelminthes.
• E) Arthropoda.

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Definitions:

Reflex

An automatic and involuntary response to a stimulus, which is a basic mechanism of the nervous system.

Curiosity

A strong desire to know or learn something, driving individuals to explore and discover new information or experiences.

Habit

A settled or regular tendency or practice, especially one that is hard to give up.

Secondary Circular Reactions

A stage in Piaget's theory of cognitive development where infants repeat actions that are pleasurable or bring about a desirable outcome.