Question

Which of the following is not associated with the phylum Echinodermata?
A. Phylum includes sea stars and sea urchins.
B. Echinoderms reproduce sexually
C. The phylum include crayfish
D. Echinoderms are heterotrophs
E. Echinoderms are invertebrates

Answer 1

Hint: In the hierarchy classification the uppermost section is the kingdom, phylum, class, order, family, genus and last is species. The number of similar characters is least in the kingdom and highest in species.

Step by step answer:The features of the organisms of the Echinodermata are as follows-
1. All the organisms of Echinodermata possess radial symmetry with a pentamerous structure.
2. It consists of external spines present on the body which are formed of the same material that of the internal skeleton.
3. They are celomatic organisms which have a water vascular system.
4. It includes mainly sea organisms.
5. Sea stars and sea urchins are the main organisms of that animal phylum along with the starfish.
6. Echinoderm reproduce by both sexually and asexually, sexually they reproduce by the external fertilization which takes place in water and asexually by the process of fission.
7. The mode of nutrition is heterotrophic. They have tubes in the feet which collect water and food and leave it in the center near the mouth of the organism In this way, they get nutrition from other organisms.
8. Echinoderms are the marine invertebrates that have both endo and exoskeleton composed of the same material.
9. They are also known as sea survival as they are found in the ocean and aquatic habitats.
10. Hence from the above detail of echinoderms we can say that the crayfish are not associated with the echinoderms.
Hence, Option C is correct

Note: Echinoderms are always found in marine water. Their habitat is marine aquatic. The crayfish is associated with the phylum Arthropoda.