Some reptiles, like snakes, have olfactory receptors on their tongues on the roof of their mouths on their skin at the tip of their tails

poor water quality affects most estuarine organisms, including commercially important fish and shellfish. the pollutants that have the greatest impact on the health of estuaries include toxic substances like chemicals and heavy metals, nutrient pollution (or eutrophication), and pathogens such as bacteria or viruses.

they deliver oxygen to the blood