Question

In which group of animals coelom is filled with blood?

• A. Arthropoda
• B. Annelida
• C. Nematoda
• D. Echinodermata

Answer 1

The correct option is A

Arthropoda

The correct option is A.

Explanation of the correct option:

1. In the phylum Arthropoda, the coelom is filled with blood which is called hemolymph.
2. Arthropods have an open circulatory system and thus they do not have any blood vessels.
3. Their blood moves or circulates in the coelom, in the form of hemolymph.

Explanation of the incorrect options:

Option B:

Annelids have a closed circulatory system and their blood circulate in the blood vessels.

Option C:

Nematodes do not have any sort of circulatory system, the gaseous exchange in them takes place through the skin.

Option D:

Echinodermata do not have any blood or heart rather they perform the gaseous exchange with the help of the water vascular system.

Final answer: In Arthropoda coelom is filled with blood.