Specialized Respiratory Structures in Animals | Zoology
In some land invertebrates and some aquatic invertebrates and vertebrates, respiratory structures to use atmospheric oxygen developed. These are tracheae, book-lung in arthropods, pulmonary sac in prosobranch and lung in pulmonate molluscs and accessory respiratory organs in fishes. 1. Tracheae and Book-Lungs: Unlike other terrestrial animals, the cells of insects obtain their oxygen supply directly from the air through a [...]