Sponge | Definition, Features, Reproduction, & Facts | Britannica
Dec 7, 2025 · Sponge, any of the primitive multicellular aquatic animals that constitute the phylum Porifera. They number approximately 5,000 described species and inhabit all seas, where they …
Characteristics and life cycle of sponges | Britannica
sponge, Any of some 5,000 species (phylum Porifera) of permanently affixed (sessile), mostly marine, solitary or colonial invertebrates, found from shallow to deep (more than 30,000 ft, or …
Sponge - Porifera, Demospongiae, & Calcarea | Britannica
Dec 7, 2025 · They belong to the phylum Porifera, which is a group of primitive multicellular aquatic animals. This classification is based on their cellular structures and biological …
Sponge - Filter Feeding, Skeleton, Reproduction | Britannica
Dec 7, 2025 · The Porifera are primarily filter feeders, utilizing food particles suspended in the water and captured by the choanocytes. Food particles consist essentially of bacteria, other …
Sponge - Anatomy, Filtering, Reproduction | Britannica
Dec 7, 2025 · Paleontological Research Institution - Digital Atlas of Ancient Life - Porifera Nature - Nature Communications - Evidence for sponges as sister to all other animals from partitioned …
Sponges Portal | Britannica
Sponge, any of the primitive multicellular aquatic animals that constitute the phylum Porifera. They number approximately 5,000 described species and inhabit all seas, where they occur …
Are Sponges Considered Animals? | Sponges, Structure, Functions ...
Dec 7, 2025 · They belong to the phylum Porifera, which is a group of primitive multicellular aquatic animals. This classification is based on their cellular structures and biological …
Cnidarian | Definition, Life Cycle, Classes, & Facts | Britannica
As first defined, coelenterates included not only the animals now designated cnidarians but also sponges (phylum Porifera) and comb jellies (phylum Ctenophora). In contemporary usage, …
Hydra | Freshwater, Cnidaria, Polyp | Britannica
Dec 5, 2025 · As first defined, coelenterates included not only the animals now designated cnidarians but also sponges (phylum Porifera) and comb jellies (phylum Ctenophora).
Sponge - Skeletal Structure, Porifera, Spicules | Britannica
Dec 7, 2025 · Sponge - Skeletal Structure, Porifera, Spicules: The skeleton of sponges is of great taxonomic significance. It may be mineral in nature or composed of protein and other …