Q. Arthropod identity card. How are arthropods characterized according to examples of representing beings, basic morphology, type of symmetry, germ layers and coelom, digestive system, respiratory system, circulatory system, excretory system, nervous system and types of reproduction?
Instance of representing beings: flies, shrimps, crabs, cockroaches, lobsters, scorpions, spiders, mites. Basic morphology: segmented body (metameric), articulated limbs, chitinous exoskeleton, periodic ecdysis. kind of symmetry: bilateral, Germ layers and coelom: triploblastics, coelomates. Digestive system: complete, Respiratory system: branchial in crustaceans, tracheal in insects, tracheal and book lungs in arachnids. Circulatory system: open, hemocyanin in crustaceans and arachnids. Excretory system: malpighian tubules in insects, green glands in crustaceans, malpighian tubules and coxal glands in arachnids. Nervous system: ganglial. Types of reproduction: sexual, with or without larval stage in insects and crustaceans, metamorphosis in some insects, no larval stage in arachnids.