Serotonin (Or 5-HT) Levels in the Leech Have Been Linked

question 48

Multiple Choice

Serotonin (or 5-HT) levels in the leech have been linked to

• A) swimming behavior.
• B) eating behavior.
• C) crawling behavior.
• D) habituation.
• E) sensitization.

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Definitions:

Hemolymph

A fluid equivalent to blood in most invertebrates, occupying the interior of their bodies and bathing their cells.

Hemocoel

Residual coelom found in arthropods, which is filled with hemolymph.

Circulatory System

The body's system responsible for transporting blood, nutrients, gases, and wastes to and from cells.

Spicules

Small, pointed structures made of calcium carbonate or silica found in sponges and some other invertebrates, serving as structural support and defense.