Question

what is characteristics of phylum arthropods?plz help me

Answer 1

Cosmopolitan in distribution found in aquatic, terrestrial and aerial forms. 
Some are ectoparasitic and vectors of disease.Body have jointed appendages or legs (which are modified to different structures to perform different functions like jaws, gills, walking legs, paddle). There may be 3 pairs, 4 pairs, 5 pairs, many pairs.Body is triploblastic.Bilaterally symmetrical.Organ system level of organization.

Answer 2

Arthropoda (Arthon- Jointed; podos- legs) It
is a phylum of triploblastic, haemocoelomic,
segmented invertebrates having head, thorax
and abdomen, a chitinous exoskeleton and
jointed legs and appendages. Most
successful phylum on the Earth that has ever
existed.