Osmoregulation: Sea Turtles

Osmosis is the diffusion of water to create equal concentrations of a solution. All organisms, whether they are terrestrial, amphibious, or marine, must osmoregulate to create an isotonic solution. An isotonic environment keeps an organisms fluids from becoming to diluted, or too concentrated, and helps animals maintain internal balance, or homeostasis.

Sea Turtles excrete salt by "crying"
and it is visible when they are out of
the water.

Salt glands are organs in reptiles and birds and help in excretion which is how they osmoregulate. Salt glands in these organisms are mainly found in the skull area; most likely in the nostrils, mouth, or eyes. The salt is moved from the blood to the glands by active transport, and then excreted as a concentrated solution. Salt glands in marine animals function in sustaining salt balance, which enables marine vertebrates to drink salt water.

The sea turtle is a marine animal which has salt glands in its eyes. The way this reptile excretes the salt it intakes is by "crying". This act is necessary for the sea turtle because unlike mammals, reptiles and birds have less efficient kidneys which means that urination would not be as helpful. Since their skin is impermeable to salt, and the assistance of excretion, sea turtles are able to dwell in saltwater environments while maintaining homeostasis.