Question

Circulatory system of Pheretima is :

• A. closed type
• B. open type
• C. both a and b
• D. none of the above

Answer 1

The correct option is A closed type

A circulatory system which involves the flow of the body fluid through vessels is called a closed type circulatory system. A circulatory system in which there are no blood vessels involved and the organs are bathed in the body fluid is called the open type circulatory system. For example : cockroaches have an open circulatory system and earthworms (Pheretima) have a closed circulatory system.