ANIMALS/INVERTEBRATES
type: Concept

SPONGES
type: Concept
definition: Sponges are multicellular organisms with no discrete tissues and organs but with a skeleton composed of collagen (with or without mineral elements), and a tubular water filtration system driven by specialized uniflagellate cells. They have a free living sessile habit and are mainly marine at all depths and latitudes but some occur in freshwater.
in scheme: sciencekeywords