Question

Choose the correct answers from the alternatives given-
To which of the following phyla do leeches belong?
a) Mollusca
b) Arthropoda
c) Echinodermata
d) Annelida

Answer 1

Hint: Leeches are parasitic worms in nature and they have a soft cylindrical body which are divided into segments. Example- earthworm. Each compartment of leeches is designed to store food and for protection of internal organs that are delicate from mechanical and external stress.

Complete answer:
d) Annelida – leeches belong to Hirudinea which is a subclass of Annelida. They are closely related to Oligochaetes. annelids have primitive brain and nerve cords which are connected to ventral and anterior ganglia and segments
So, Option D is the correct answer.

a) Mollusca- Mollusca have organisms like- ark shell, mussels, scallops, oysters, squid, clams and octopus. There are diverse animals in this group which are an important part of the ecosystem. Mollusca have three pairs of ganglia like- cerebral, pedal and pleural ganglia, which are connected to cerebra-pedal and pleuro-pedal.
Option A is not the correct answer.
b) Arthropoda- arthropods include-lobster, spider and centipedes, crabs, mites and cockroaches. Leeches nowhere belong to this phylum.
Option b is not the correct answer.
c) Echinodermata- starfishes, sea urchins, sea cucumbers are examples of echinoderms. They have spines on the surface of skin and a uniquely shaped body.
Option C is also not the correct answer.

Note:
The different phylums have been categorized equivalent to kingdom and classes because animals or organisms belong to different habitat, relationship, their body symmetry etc. all organisms can not be under one taxonomic category. For better understanding organisms have been kept under taxonomical aids.