Phylum Porifera Sponges Phylum Porifera pore bearersponges o
Phylum Porifera Sponges
Phylum Porifera (“pore bearer”)sponges o Characteristics: Sponges are sessile (don’t move) n Sponges grow in many sizes, shapes and colors n Sponges can be encrusting, boring, vaselike, treelike, and can be several meters in diameter n
Specific Types: o Encrusting - flat, soft, found on rocky shores and tide pools o Tubular - vase-shaped, hard, found in calm tropical waters & coral reefs o pecten sponge - soft, has a mutually symbiotic relationship with a bivalve mollusk (scallop) -sponge grows on the scallop’s shell, completely covering the shell. sponge gets a place to live and more water to filter -the scallop gets protection- something may try to bite the scallop and will just scrape off sponge and the sponge will regenerate. o boring sponge - bores holes into the shell of the gastropod (snail ) called an abalone and eats the abalone (parasitic)
Sponge Anatomy o Sponges have skeletons made of spongin (flexible), spicules (prickly), or both n Sponges can be identified by the composition of the spicules (siliceous -Si spicules, calcareous-Ca spicules) n Sponges have tiny pores on the outside called porocyte cells (water comes into the sponge here)
Sponge Anatomy cont… o Epithelial cells cover the outside of the sponge o A large opening (pore) is the osculum, where the water exits the sponge o Collar cells with flagella set up a current by beating whip tails, which bring water in the pore cells and out the osculum o Amoebocyte cells transport and digest nutrients, while also making spicules (act as amoebas within sponge body)
Sponge Digestion o Sponges have NO digestive system, only digestive cells o Sponges feed on detritus (bacteria, plankton, animal matter) by filter feeding o Food is trapped by the collar cells, while the amoebaocytes distribute the nutrients o Wastes are expelled through the osculum
Sponge Reproduction o Sponges can reproduce sexually and asexually n n n Sexually- shed sperm & eggs into the water (hermaphroditic) Asexually- budding & gemmules Sponges also have amazing powers of regeneration
Sponge Symbiotic Relationships o Sponges often form symbiotic relationships (live in close association with another species) n n n Mutualism- Commensalism- : I Parasitism-
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