Question

Which one of the following phyla is correctly matched with its two general characteristics?

• A. Echinodermata - Pentamerous radial symmetry and mostly internal fertilization
• B. Mollusca - Normally oviparous and development through a trochophore or veliger larva
• C. Arthropoda - Body divided into head, thorax and abdomen and respiration by tracheae
• D. Chordata - Notochord at some stage and separate anal and urinary openings to the outside

Answer 1

The correct option is C Arthropoda - Body divided into head, thorax and abdomen and respiration by tracheae

Arthropoda is the largest phylum of kingdom Animalia that characteristically possess an outer body layer - the cuticle. The body is composed of segments usually forming distinct specialized body regions i.e. is the head, thorax, and abdomen. Respiratory organs consist of book gills or gills in the aquatic and semi-aquatic arthropods and book lungs or trachea in the terrestrial forms.