Frogs may breathe through their skin or using their lungs. Oxygen from air or water is dissolved into the frog's thin skin and diffused through the walls of the blood capillaries into the blood stream. When on land, frogs are able to breathe through their lungs simultaneously with their skin. The lungs are a much more efficient way for frogs to acquire oxygen. Frogs do not have to breathe rhythmically as most animals do, instead taking in oxygen only as needed. Frogs have nasal valves to prevent the intake of water into lungs when swimming.
A frog's skin is covered with a protective mucus to keep it from drying out. Frogs replace their skin weekly by pulling off old skin to reveal new skin underneath.This regeneration process ensures that the skin stays soft and efficiently coated with the protective mucus.
Frogs have webbed feet that allow them to move through the water more efficiently. Their strong hind legs help them to swim and leap more efficiently. They have excellent vision to allow them to see in poor conditions, such as murky water and nighttime.