Notes from NEET topper
Phylum- Arthropoda
• Largest phylum (includes insects).
•Segmentation-present.
•Skeleton-exoskeleton is of Chitin.
•Body division-head, thorax, abdomen.
•Locomotion-by jointed appendages.
•Respiration-by gills, book gills, book lungs, tracheal system.
•Circulatory system-open.
•Sensory organs-antennae, compound & simple eye,statocysts/balance organs are found.
•Excretion-through malphigian tubules.
•Reproduction-dioecious Fertilisation-usuallyinternal (oviparous) with direct or indirect development.
•Eg- Economically useful- Apis(honeybee),Bombyx (silkworm),Laccifer (lac insect)
•Vectors- Anopheles, Culex, Aedes (Mosquitoes)
• Gregarious pest-Locusta(locust).
• Living fossil-Limulus (king crab)
