Sponges

Phylum: Porifera

Description: They are multicellular animals, with tremendous diversity in size and shape resulting from different growth patterns in various environments. Sea sponges are generally asymmetrical, and their colors range from blue to yellow, and crimsons.

Distribution: They are found in the benthic marine environment, from lower inter-tidal to great depth, but mainly in unpolluted littoral habitats.

Locomotion: Sessile.

Food gathering & Gas exchange: They are suspension feeders-utilize flagellated cells called choanocytes to circulate water through unique system of water canals. Water comes in though ostia bringing with it oxygen and planktonic of detritic food and flows out through a single osculum or multipile oscula, carrying away carbon dioxide and wastes.

Reproduction: They are capable of asexual reproduction by regenerating adults from fragments. For sexual reproduction, most are hermaphroditic, producing eggs and sperm at different times, thus animals can change sex once or more than once. However, Sponges lack distinct localized gonads. Sperm is released through the water system (can result in ‘smoking’sponges) and is taken in to neighbouring sponges. The larval stage is planktonic, and short (just a few days)

Interesting facts: Sponges’ primary defense is biotoxins, some of which are quite potent.