Skeletal Elements Found in Sponges | Phylum Porifera

The following points highlight the two main skeletal elements found in sponges. The types are: 1. Spongin 2. Spicules. Skeletal Element: Type # 1. Spongin: The spongin comprises of fi­bres of spongin and they resemble silk in appearance. These are proteinaceous secre­tion of the spongioblasts and form a net­work. In most cases, the spongin fibres are composed of protein, termed [...]