Question

The anterior portion of the body of most annelids, such as the earthworm, is adapted for sensing the environment.

Answer 1

Answer:

The answer is False. Although sensitive cells are more abundant in the anterior portion of the annelid´s body, in general, they are arranged in all the segments.

Explanation:

Annelids, such as the earthworm, have a variety of sensory cells:    

• Mechanoreceptors, disposed of in groups in each segment of their body.  

• Photoreceptors: Light-sensitive cells. Although they are located in the whole body, they are abundant in anterior and posterior segments, concentrated in the intern and dorsal part of the epidermis.

• Humidity receptors are the most sensitive cells and are located in the first segments of the earthworm body

• Chemoreceptors: sensorial cells cumulus forming a prominent tubercle with prolongations that extends through the cuticle. These tubercles form three rings in each segment but are especially abundant in the anterior part of the body.

The tegument is very rich in free nervous terminations, which functions might be tactile.