Why do reptiles have cold blood?

snakes are cold blooded because they are reptiles and have scales, if they were warm blooded they couldnt have scales and the venom keeps the venom poison..< What the crap? no dude.

reptiles have cold blood because their internal organs do not need to be warm to function smoothly, and correctly. unlike mammels that generate our own body heat because we do need warm organs to operate smoothly.

Cold-blooded animals, like reptiles, amphibians, and fish, become hotter and colder, depending on the the temperature outside. For example, when the sun sets at night, their bodies are cooler because it is less warm outside. When the sun is out, however, their bodies soak up the heat and become warmer.