Cephalization, the Clustering of Neurons and Interneurons in the Anterior

question 4

Multiple Choice

Cephalization, the clustering of neurons and interneurons in the anterior part of the animal, is apparent in

• A) Hydra.
• B) cnidarians.
• C) Planaria.
• D) sea stars.
• E) invertebrate animals with radial symmetry.

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Definitions:

Reticular Activating System

A network of neurons located in the brainstem that plays a crucial role in regulating wakefulness and sleep-wake transitions.

Alert

A state of active attention or vigilance that enables an individual to be ready to respond to certain stimuli or situations.

Thalamus

A part of the brain that serves as a relay station for sensory and motor signals to the cerebral cortex.

Touch

A sensation perceived through the skin, involving physical contact and often associated with emotional and social communication.