EVERYDAY SCIENCE

Detailed explanation-1: -People, polar bears, penguins, and prairie dogs, like most other birds and mammals, are endotherms. Iguanas and rattlesnakes, like most other reptiles-along with most fishes, amphibians, and invertebrates-are ectotherms. Endotherms generate most of the heat they need internally.

Detailed explanation-2: -endotherm, so-called warm-blooded animals; that is, those that maintain a constant body temperature independent of the environment. The endotherms primarily include the birds and mammals; however, some fish are also endothermic.

Detailed explanation-3: -In vertebrates, endothermy is typically associated with birds and mammals while fishes, amphibians, and reptiles are generally typified as ectotherms. However, there are representatives in the latter group whose body temperature can be significantly influenced by thermogenesis.

Detailed explanation-4: -Virtually all mammals are endothermic. Endothermy is the ability of an organism to generate and conserve heat in order to maintain a stable, warm body temperature. This ability is commonly referred to as warm-bloodedness.

Detailed explanation-5: -Reptiles and amphibians are ectotherms, while birds are endotherms. An ectotherm (reptile/amphibian) relies primarily on its external environment to regulate the temperature of its body. Endotherms (birds) are able to regulate their body temperatures by producing heat within the body.