EVERYDAY SCIENCE

Detailed explanation-1: -All arthropods posses an exoskeleton, bi-lateral symmetry, jointed appendages, segmented bodies, and specialized appendages. The major arthropod classes can be separated by comparing their number of body regions, legs, and antennae. Class Crustacea (crus-ta-ce-uh), the crustaceans. This is a very diverse class.

Detailed explanation-2: -(i) True coelom is a body cavity which arises as a cavity in the embryonic mesoderm. (ii) Digestive cavity is found in acoelomates, pseudocoelomates as well as coelomates. (iii) The body cavity of arthropods and non-cephalopod molluscs is called haemocoel.

Detailed explanation-3: -arthropod, (phylum Arthropoda), any member of the phylum Arthropoda, the largest phylum in the animal kingdom, which includes such familiar forms as lobsters, crabs, spiders, mites, insects, centipedes, and millipedes.

Detailed explanation-4: -insects; myriapods (including centipedes and millipedes); arachnids (including spiders, mites and scorpions); crustaceans (including slaters, prawn and crabs).