Question

Select the taxon mentioned that represents both marine and freshwater species?

• A. Ctenophora
• B. Cephalochordata
• C. Echinoderms
• D. Cnidaria

Answer 1

The correct option is D

Cnidaria

The correct option is D.

Explanation of correct option:

1. In Cnidaria, the organisms are mainly marine except for Hydra which is a freshwater form.
2. They have radial symmetry.
3. They are diploblastic animals.
4. They have a tissue level of organization.
5. They have special stinging cells called cnidoblasts that help to capture food, attack their prey, and adhere to surfaces.

Explanation of incorrect options:

Option A:

1. Ctenophora are a small group of marine animals.
2. They have biradial symmetry.
3. They are luminescent as they have light-producing photocytes.

Option B:

1. Cephalochordata is a subphylum of the phylum Chordata.
2. They are marine animals.
3. They have a notochord that persists throughout their life.

Option C:

1. Echinoderms are spinny-skinned marine organisms.
2. They have a radially symmetrical body.
3. They are triploblastic and have an organ system level of organization.

Final answer: The taxon that represents both marine and freshwater species is Cnidaria.