What digestive system do cnidarians possess?

• A. Gastrovascular Cavity
• B. Complete Digestive Tract
• C. No Digestive System
• D. Alimentary Canal

Answer: (A)

Cnidarians rely on a single, sac-like compartment called the gastrovascular cavity. This space serves as both the entry point for food and the exit for indigestible material, so there is one opening that acts as both mouth and anus. Inside, digestion occurs extracellularly in the cavity and nutrients are then taken up by cells lining the cavity. Because there isn’t a tube with two separate openings, they don’t have a complete digestive tract or an alimentary canal. This makes the gastrovascular cavity the appropriate description of their digestive system.