Question

A circulatory system is said to be closed when blood flows through tubes called blood vessels.

• A. True
• B. False

Answer 1

Answer: (A)

True

A circulatory system is said to be closed when the blood flows only through a network of blood vessels, like in humans. The open circulatory system is present in animals like cockroaches where blood flows through the body cavity. No blood vessels are present in these animals.