How Do Reptiles Obtain Oxygen?

Reptiles are cold-blooded vertebrates that lay eggs. Cold-blooded means that the reptile's blood takes on the temperature of its environment. If a reptile's blood becomes too warm after the animal has been out in the sun, it cools off by submerging its body in water or mud to help bring down its blood temperature. Vertebrates are animals that have spines, like humans. In many reptiles, the spine is made of highly flexible cartilage, which allows the reptile to move more freely than animals with more solid spines. All four classes of reptiles--turtles, lizards, snakes and crocodilians--are oviparous, meaning that they lay eggs to reproduce. Some rare species of snakes are also viviparous, meaning that they can give birth to live young, and others reproduce parthenogenetically, meaning that female snakes can reproduce without fertilization by a male.

  1. Reptile Lungs

    • All reptiles obtain oxygen the same way humans do: by breathing it in through their noses and mouths into their lungs. However, some species can also obtain oxygen through different means, including through their skin, mucous membranes near the mouth and through gills.

    Turtles

    • Turtles breathe through their mouths and noses into a pair of lungs. However, they also store oxygen in their cloacas, the same tract used for expelling waste. By storing oxygen in more than one place in their bodies, turtles can go for long periods of time--up to weeks when they are hibernating in cold weather--without having to surface to breathe.

    Lizards

    • Lizards obtain oxygen by breathing through the mouth and nose into lungs. Some lizards, like salamanders, also get oxygen by extracting it from water sucked through a membrane in the mouth. Lizards that live in wet, hot climates and near large bodies of water obtain oxygen through a combination of lung breathing and membrane filtering.

    Snakes

    • Snakes have a single functioning lung, usually on the right side of their bodies. Some snakes may also have very small, nonfunctioning left lungs. Snakes breathe in oxygen through their nostrils into their lungs.

    Crocodilians

    • Crocodilians, which include both crocodiles and alligators, obtain oxygen in two ways. When they are out of the water, or have their heads above the water, they breathe through the nostrils into lungs. However, when they are submerged or have their jaws open underwater, bony openings on the sides of their throats called palatal valves allow them to take in air while keeping out water.