Visceral mass

Definition

The visceral mass is the central section of a mollusk's body that contains most of the internal organs such as the heart, digestive organs, excretory organs, and reproductive organs. It is distinct from the foot and mantle in these organisms.

5 Must Know Facts For Your Next Test

1. The visceral mass houses essential systems like the circulatory, digestive, excretory, and reproductive systems.
2. It is typically enveloped by the mantle, which secretes the shell in many mollusks.
3. The visceral mass varies greatly in shape and complexity among different classes of mollusks.
4. In cephalopods like octopuses and squids, the visceral mass is more compact compared to other mollusks.
5. Gastropods exhibit torsion during development, where the visceral mass twists up to 180 degrees.

Review Questions

Related terms

Mantle: A significant part of a mollusk that covers and protects its internal organs and often secretes the shell.

Foot:

A muscular structure used primarily for locomotion in many mollusks.

Radula: A specialized feeding organ in mollusks, often referred to as a 'tongue' with teeth used for scraping or cutting food before ingestion.