AP BIOLOGY

Detailed explanation-1: -Endoskeleton. An endoskeleton is a skeleton that consists of hard, mineralized structures located within the soft tissue of organisms. An example of a primitive endoskeletal structure is the spicules of sponges. The bones of vertebrates are composed of tissues, whereas sponges have no true tissues ([link]).

Detailed explanation-2: -External skeletons, or exoskeletons, are the hard casings that protect arthropods, such as insects, crustaceans, and spiders. This natural armor is a very effective defense against predators, many of which can’t bite through the exoskeleton, Huskey says.

Detailed explanation-3: -There are three different skeleton designs that provide organisms these functions: hydrostatic skeleton, exoskeleton, and endoskeleton.

Detailed explanation-4: -Insects are the largest group of animals that have an exoskeleton. Insects have exoskeletons made of a substance called chitin. The exoskeletons of crabs, lobsters, shrimp, spiders, ticks, mites, scorpions, and related animals are also made of chitin.

Detailed explanation-5: -An exoskeleton is a key feature of arthropods, a category of animals that includes insects, spiders, and crustaceans. Grasshoppers, cockroaches, ants, bees, cicadas, scorpions, lobsters, shrimp, black widows, snails and crabs are all examples of animals with exoskeletons.