AP BIOLOGY

Detailed explanation-1: -A species is classified as endangered when there are fewer than 2, 500 mature individuals. When a species population declines by at least 20 percent within five years or two generations, it is also classified as endangered.

Detailed explanation-2: -Under the Endangered Species Act (ESA), plant and animal species may be listed as either endangered or threatened. “Endangered” means a species is in danger of extinction throughout all or a significant portion of its range. “Threatened” means a species is likely to become endangered within the foreseeable future.

Detailed explanation-3: -An endangered organism is one that is close to extinction due to the fact that its numbers are declining. On the other hand, an endemic organism is one that lives in a particular region and nowhere else on earth.

Detailed explanation-4: -An animal is called endangered when there are so few of its kind left that it is in danger of becoming extinct-disappearing from the world forever. There are many reasons that animals and plants can become endangered or die out altogether. Since Earth began 4.5 billion years ago, it has been continually changing.

Detailed explanation-5: -Endangered species: These are the species that are in danger of extinction.