EVERYDAY SCIENCE

Detailed explanation-1: -Bilateral symmetry, triploblastic nature and metamerism are seen in both Annelida and Arthropoda. However, arthropods possess an open vascular system, while annelids possess a closed type.

Detailed explanation-2: -The vast majority of animals display bilateral symmetry; also known as plane symmetry, this is a trait that applies to 99% of all animals, in the majority of phyla: Chordata, Annelida, Arthropoda, Platyzoa, Nematoda, and most Mollusca.

Detailed explanation-3: -Examples of animals that possess bilateral symmetry are: flatworms, common worms ("ribbon worms"), clams, snails, octopuses, crustaceans, insects, spiders, brachiopods, sea stars, sea urchins, and vertebrates.

Detailed explanation-4: -Mollusca can be found in freshwater, marine and terrestrial habitats. More features of molluscs include bilateral symmetry, soft or unsegmented bodies, respiration via ctenidium, ganglia/nerve comprised nervous system, haemocoel body cavity, etc.

Detailed explanation-5: -Annelids and arthropods are bilaterally symmetrical, that is, the body can be divided into two identical halves only along one imaginary plane.