Question

Choose the correct answer from the alternatives given.
Which of the following is the part of a closed, but not an open, circulatory system?

• A. Heart
• B. Haemocoel
• C. Capillary beds
• D. Ostia

Answer 1

The correct option is C Capillary beds

In an open circulatory system, the blood is not confined within blood vessels. The blood bathes the organs and tissues directly. Because of this the blood and the interstitial fluid have no distinction. Thus, the term hemolymph is used. The hemolymph is pumped by the heart through the vessels into the sinuses and then to the surrounding cells where the exchange of materials occur. The hemolymph is taken back to the heart through the ostia that close via the valves during heart contraction.

So, the correct option is 'Capillary beds'.