Question

write some characteristics of Arthropoda and Mollusa​

Answer 1

Appendages on at least one segment. ...

A nervous system

Answer 2

Arthropoda:-

Arthropods are joint-legged animals and you must have come across a few of these animals. Some prominent ones include insects, spiders, ants, bees, crabs, shrimps, millipedes, centipedes etc. Scientifically speaking, they all come under the Animal Kingdom

Mollusca:-

The most general characteristic of molluscs is they are unsegmented and bilaterally symmetrical. The following are present in all modern molluscs: The dorsal part of the body wall is a mantle (or pallium) which secretes calcareous spicules, plates or shells.

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