Question

This belongs to the phylum cnidaria
(a)Sea anemone
(b)Sycon
(c)Chalina
(d)Amoeba

Answer 1

Hint: They are aquatic organisms (saline), which are predatory in nature and belong to the order Actiniaria. The complete hierarchy includes phylum - Cnidaria, class - Anthozoa, and subclass - Hexacorallia. They are linked to corals, jellyfish, and Hydra.

Complete answer:
Sea anemone comes under the class of Anthozoa in the phylum Cnidaria. Sedentary and polypoid is the form in which they are present. Vertical septa divide Coelenteroninto into several compartments known as the mesenteries. Cnidocytes take place in ectoderm and endoderm differentiate into germ cells.

Additional Information:
-The base of the sea anemone is attached to the strong bottom surface by a single polyp, but living in soft sediment soil and floating freely near the ocean surface is also shown by some species.
-The central mouth is surrounded by a ring of tentacles and an oral disk below the columnar polyp.
-To catch prey they use their extendable tentacles which they retract and inside when they are not using it. Cnidocytes or the stinging cells helps many species to survive, also the symbiotic relationship with zooxanthellae or cells come provides additional nourishment
-Symbiotic relationship with hermit crabs, small fish, and other marine animals are also seen in some species for mutual benefit.
So, the correct answer is ‘Sea anemone’.

Note: -Sea anemones fertilize eggs by releasing sperm and eggs into the sea through the mouth and results in the formation of planula larvae which will later sediment on the bottom of the sea and grow into juvenile polyps.
-Asexual reproduction of sea anemones is by regeneration where they breaking in half or into fragments which later grow into polyps.
-The expanding trend and interest in marine ornaments increased the global demand for sea anemones which threatens their existence along with the rapidly increasing pollution.