Question

Open vascular system is absent in

• A. Housefly
• B. Cockroach
• C. Silver Fish
• D. Earthworm

Answer 1

The correct option is D Earthworm

Pheretima exhibits a closed vascular system, consisting of blood vessels, capillaries, and heart. Due to the closed circulatory system, blood is confined to the heart an blood vessels. Contractions keep blood circulating in one direction. Smaller blood vessels supply the gut, nerve cord, and the body wall.

Hence earthworm has closed blood vascular system.

So the correct answer is 'Earthworm'.