Explain the structures of respiratory organs for the exchange of gases in various groups/kingdoms of animals.

(N/A) Mechanisms of breathing vary among different groups of animals,depending mainly on their habitats and levels of organization. Simple organisms exchange gases by simple diffusion over their entire body surface,while complex organisms have evolved specialized respiratory organs.

$1$. Animal Group	$2$. Respiratory Organ
Lower Invertebrates (Porifera,Coelenterata,Platyhelminthes)	Entire body surface (Diffusion)
Annelida	Moist cuticle (Cutaneous respiration)
Arthropoda (Insects)	Tracheal system
Arthropoda (Aquatic - Crustaceans)	Gills (Branchial respiration)
Arthropoda (Arachnids)	Book lungs/Book gills
Mollusca	Gills (Ctenidia)
Echinodermata	Tube feet/Dermal branchiae
Amphibians	Moist skin,lungs,and buccal cavity
Reptiles,Birds,Mammals	Lungs (Pulmonary respiration)
Fishes	Gills