Question

Which of the following is the correct matching set of Phylum and its three examples?
A. Annelid – Nereis, Pheretima and Apis
B. Echinodermata – Ophiura, Antedon and Cucumaria
C. Mollusca – Dentalium, Pinctada, Hirudinaria
D. Aschelminthes – Ancylosytoma, Wuchereria and Asterias

Answer 1

The hierarchical system of classification was done by Whittaker which is followed today generally. It divides organisms into rankings. As we go down the hierarchy, the specifications increase and the number of animals decreases. As we go up the hierarchy, the number of species increases.

Complete answer:
The classification system followed today describes the animal into various ranks including kingdom, phylum, orders etc. Kingdoms are Plantae, Animalia, Protists, Fungi and monera.
The new 3 kingdom classification is also studied now, which is given by Carl Woese. It has 3 domains – Eubacteria, Archaebacteria and Eukarya.
The various phyla in animal kingdom classification are – Porifera, Cnidaria, Platyhelminthes, Annelida, Mollusca, Arthropoda and Chordata.
Option A: Annelid – Nereis, Pheretima and Apis: Nereis, Pheretima belong to phylum annelida but Apis belong to Arthropoda phylum.
Option B: Echinodermata – Ophiura, Antedon and Cucumaria: Ophiura belongs to Echinodermata phylum and class Ophiuroidea. Antedon belongs to the phylum Echinodermata and class Crinoidea. Cucumaria belongs to the phylum Echinodermata and class Holothuroidea.
Option C: Mollusca – Dentalium, Pinctada, Hirudinaria: Dentalium, Pinctada belong to Mollusks but Hirudinaria belongs to phylum Annelida.
Option D: Aschelminthes – Ancylosytoma, Wuchereria and Asterias: Asterias belong to Echinodermata but the Ancylosytoma, Wuchereria belong to aschelminthes that are roundworms.

Hence the correct answer is OPTION(B)

Note: Ophiura is a serpent star or brittle star in phylum Echinodermata. Antedon is the free-swimming crinoids which are stemless. Cucumaria is the sea cucumber which is found in the freshwater bodies. Echinoderms are usually star-shaped or spherical creatures. They have an organ level of organization. Calcium carbonate makes up their skeleton. They are exclusively marine animals.