sponge: Quick Facts

Written and fact-checked by

The Information Architects of Encyclopaedia Britannica

Facts

Also Known As	poriferan • Porifera

Photos and Videos

freshwater sponge (Spongilla)

freshwater sponge

multicellular animal

Figure 33: (Top) A colony of three species of sponges, approximately three-quarters of life size. At top of colony is a small bread-crumb sponge (Halichondria); branching mass at right is leucosolenia complicata; tubular sponges on left are Scypha cilia

(Top) Spongia, (centre) Hippospongia communis, and (bottom) Spongia

Illustration showing different animals and their respiratory organs: a spider with book lungs, a chicken with lungs, a sponge with labeled inflow and outflow pores, a fish with gills, and a caterpillar with spiracles.

A simple saclike sponge. Its surface is perforated by small openings (incurrent pores) formed by tubelike cells (porocytes), which open into the internal cavity. A gelatinous middle layer contains the skeletal elements (spicules and spongin fibers) as well as amebocytes active in digestion, waste removal, and spicule and spongin formation. Flagellated collar cells (choanocytes) line the internal cavity, create currents to move water containing oxygen and food into the sponge, and engulf and digest food particles. Water and wastes are expelled through the ostium opening, whose size can be altered to regulate water flow through the sponge.

Exploring underwater caves at Calanques National Park

See All Videos and Images →

Topics

Axinella archaeocyathid Are sponges considered animals?siliceous sponge calcareous sponge glass sponge Suberites domuncula Tedania ignis Calcaronea Calcinea annelid echinoderm flatworm cnidarian arthropod mollusk moss animal lamp shells beard worm arrowworm

Dig Deeper: More Articles That Discuss This Topic

Key People

Bowerbank

James Scott Bowerbank

British naturalist and paleontologist

Mushrooms growing in forest. (vegetable; fungus; mushroom; macrofungi; epigeous)

Science at Random Quiz

Lion (panthera leo)

Deadliest Animals Quiz

The bearded vulture (Gypaetus barbatus) is seen in Switzerland on December 2024

Animal Factoids

Mute swan with cygnet. (birds)

Match the Baby Animal to Its Mama Quiz

Sea otter (Enhydra lutris), also called great sea otter, rare, completely marine otter of the northern Pacific, usually found in kelp beds. Floats on back. Looks like sea otter laughing. saltwater otters

Animal Group Names