i? The book provides a comprehensive and up-to-date account of the information available on the morphological, physiological and evolutionary aspects of specialized cells distributed within the epithelia of the airways in the vertebrates. A lot of work has been done on the cell and molecular biology of these cells which are regarded as as oxygen receptor neuroepithelial cells. These chemoreceptors which were conserved throughout evolution have neuroendocrine functions carrying their signals to the central nervous system.i? The chemoreceptor cells are sensors which detect the signal changes in the external and internal environments, and play a key role in the survival of various species. Studies addressed to the chemoreceptor cell systems in the airways are of great importance for investigating their response to changes in the oxygen and carbon dioxide concentrations in the environment since the future of the planet earth is being threatened by global warming and climate change.