Frogs are amphibians, their life is very closely related to water. In Russia, two types of frogs are most often found - grass and sharp-faced. The respiration of these animals is carried out through the lungs and also through the skin.
How the frog breathes
The frog's lungs are underdeveloped, therefore, both in water and in air, it breathes mainly on the surface of its body. Through the lungs, breathing in frogs is carried out as follows: the bottom of the oral cavity descends, through the open nostrils, air enters inside. Then the abdominal muscles squeeze out the rest of the exhaust air, while the bottom of the mouth continues to fall. After that, the nostrils close, the floor of the mouth rises and pushes air into the lungs.
Having gained a supply of air, the frog dives into the water. Oxygen from the lungs begins to slowly be absorbed into the blood. This allows her to stay underwater long enough. After the supply of oxygen from the lungs is used up, the frog emerges to the surface. However, it can receive oxygen through the skin. Experts conducted research to find out how long a frog can be in the water without coming up. It turned out that a toad can spend about eight days in the water, and a grass frog - almost a month.
In order for the skin of the frog to pass oxygen well, its surface must always be moist. Therefore, amphibians living on land love damp habitats. They hunt insects at dusk and at night, and during the day they hide from the sun under grass and leaves. Frogs feel cold to the touch, because water evaporates easily through thin skin and cools its surface. The body temperature of these amphibians is always several degrees lower than the ambient temperature.
Water also penetrates the frog's body through the skin. The frog does not need to drink water, it is enough for it to press its abdomen against damp ground, plants or swim in the dew.
How a frog hibernates
Breathing through the skin is very important for grass frogs, as they hibernate, burrowing in silt at the bottom of water bodies. Ponds in winter do not freeze to the very bottom, even at very low temperatures, so frogs do not freeze either. With the onset of autumn, amphibians fall into a state of suspended animation, in which all life processes slow down. The amount of oxygen they need decreases, and the frog has enough skin respiration.
Like all cold-blooded frogs, they have a reduced energy exchange. Their activity will directly depend on the ambient temperature.
Sharp-faced frogs, unlike grass frogs, spend the winter on land. They are hammered under stones, driftwood, leaves, in mouse and wormholes. Hibernation of amphibians lasts 150-200 days and depends on the duration of the cold period. In winter, a significant part of them die; by spring, only 2-5% of frogs remain.
