Endoskeletonit

Endoskeletonit refers to an internal skeletal system. This type of skeleton is found in vertebrates, such as mammals, birds, reptiles, amphibians, and fish, as well as some invertebrates like echinoderms. Unlike exoskeletons, which are external coverings, endoskeletons provide structural support from within the body. They are typically composed of bone and cartilage in vertebrates, and calcareous plates or spicules in some invertebrates. The primary functions of an endoskeleton include providing a framework for the body, protecting vital organs, allowing for movement through muscle attachment, and producing blood cells in the marrow of bones. Growth in animals with endoskeletons occurs through the addition of new material to the internal structure, rather than molting as seen with exoskeletons. This internal support system allows for greater flexibility and a wider range of motion compared to rigid external skeletons.