 Dear students, in this topic we shall discuss the respite responses of animals to diving. Many air-breathing equate equative rates, for example dolphins, whales and water birds, they go underwater for varying periods of time. This duration of submersions is termed as a dive. Diving animals have to come back to the surface after some time so that they can breathe. The time between breath varies with the animals. For most divers, this time is around 10-20 minutes. This usually does not happen without a breath in the water. Dear students, Diving animals, when they are in the process of diving, they are subjected to periods of hypoxia and anoxia. Hypoxia means that oxygen is not available, but anoxia means that oxygen is not available. Mammals' central nervous system cannot tolerate anoxia. It must be supplied with oxygen throughout the dive. Diving animals utilize oxygen stores in their lungs, blood and tissues to supply oxygen to critical tissues. Most diving animals have high hemoglobin as well as myoglobin content. Myoglobin stores oxygen in them, which is useful for such periods of time. Oxygen is preferentially delivered to brain and heart. Blood flow to other organs is reduced and they use anaerobic metabolic pathways. Prolonged divers have more time to understand. For example, elephant seals reduce their metabolic rates and reduce their oxygen requirements. Dear students, During diving, another problem and another control is that animals do not exhalation during the diving process. How is this controlled? For this, there are specialized receptors which detect the presence of water. They inhibit inspiration during a dive. Such receptors are situated in glottis, mouth or nose. They are located in the mouth according to the species. When oxygen level decreases in blood and carbon dioxide level increases, then ventilation is stimulated in divers. This is the same position. But despite this, such response is not produced. It is because the inputs from chemo receptors of kerotid and aortic bodies which increase the ventilation rate are ignored by the respite neurons in submerged state.