Phylum – Phylum – PoriferaPorifera

The SpongesThe Sponges

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The Sponges – Phylum Porifera

TaxonomyTaxonomy

• Kingdom – AnimaliaAnimalia•Subkingdom – ParazoaParazoa (lacks tissues)

•Phylum – PoriferaPorifera (pores)

CharacteristicsCharacteristics

o Porifera Porifera Porus (pore) + Fera (bearing)

o SimplestSimplest of all animalso Contain specialized specialized

cellscells but no other organization level

o Most are marinemarineo Saltwater sponges are

brightly coloredbrightly colored

CharacteristicsCharacteristics

o Freshwater spongesFreshwater sponges are small and dull green color

o Size – 2 meters to 2 cm2 meters to 2 cmo No nerves - therefore -

No coordinated movement

o Single or colonial

CharacteristicsCharacteristics

o WaterWater enters through pores bringing in food food and oxygenand oxygen

o Filter feedersFilter feeders on plankton

o OsculumOsculum – large opening at the top where excess water leaves

Draw or trace diagram of a sponge

from page 131 in your text book

Water FlowWater Flow Through the Through the

SpongeSponge

WATER INWATER IN

WATER OUTWATER OUT

OsculuOsculumm

CharacteristicsCharacteristics

o AsymmetricalAsymmetricalo Sessile Sessile as adults

(attach to rocks)o Free-swimming

larval stage called DipleurulaDipleurula

o Also reproduce by fragmentation fragmentation (pieces break off & form a new sponge)

Sponge Body StructureSponge Body Structure

o Inside body cavity of sponge is hollowhollow

o Called the SpongocoelSpongocoelo Have 2 cell layers:

Outer epidermisepidermis Inner endodermendoderm

o Jelly-like material between cell layers called mesenchymemesenchyme

•Collar Cells Collar Cells line the gastrovascular cavity & capture food

•AmebocytesAmebocytes digest & distribute food

Collar cells Collar cells

Specialized CellsSpecialized Cells• Collar cells line inside

of body cavity (spongocoel)

• Have flagellaflagella that spins to pull in water & food

• CollarCollar traps diatoms, diatoms, protozoans, bacteria protozoans, bacteria and organic matterand organic matter (food) from water

Collar

Collar cells

o Amebocytes:Amebocytes:•Pick up foodPick up food from

collar cells•Finish digestiondigestion•MoveMove through the

mesenchyme & take food to other cells

Other Specialized CellsOther Specialized Cells

Skeletal Structure of the Skeletal Structure of the SpongeSponge

•Skeleton made of network of protein fibers called SponginSpongin

• SpiculesSpicules are hard spear or star-shaped structures

•Spicules made of CaCOCaCO33 (limestone) or silicasilica SiOSiO22(glass)

Sponge SkeletonsSponge Skeletons

SPONGINSPONGIN

Silica SpiculesSilica Spicules

Limestone SpiculesLimestone Spicules

Sponge SkeletonsSponge Skeletons

SPICULESSPICULESVENUS VENUS FLOWEFLOWE

R R BASKETBASKET

Spicule type determines classification

Phylum Porifera

Class:

Calcarea (calcerous sponges having spicules)

Phylum Porifera

Class:

Demosponginae

(horn sponges, like the bath sponge)

Phylum Porifera

Class:

Scleropongiae

(coralline or tropical reef sponges)

Phylum Porifera

Class:

Hexactinellida

(glass sponges).

Sponge ReproductionSponge Reproduction

oSponges can regenerateregenerate (regrow) lost body parts through mitotic cell division (asexual)

oSponges also reproduce asexually asexually by buddingby budding

Sponge ReproductionSponge Reproduction

oSponges are hermaphrodites hermaphrodites (produce both eggs & sperm)

oSponges reproduce Sexually Sexually by releasing releasing eggs & sperm eggs & sperm into the water from the from the OsculumOsculum

o Cross-fertilize Cross-fertilize each other’s eggs

Sponge releasing

eggs & sperm

Surviving Harsh ConditionsSurviving Harsh Conditions

o GemmulesGemmules are specialized buds made to survive harsh weather (hot or cold)

oContain food, amebocytesfood, amebocytes, and a protective covering protective covering of spicules

oReleased when a sponge diessponge diesoResist dessicationdessication (drying out)oBecome adult sponge conditions conditions

become favorablebecome favorable

FeedingFeeding

o Filter FeedersFilter FeedersoCollar cells collect particles as

they pass through the Pore Cells

oItems consumed are Resist d d diatoms, protozoans, bacteria diatoms, protozoans, bacteria and organic matterand organic matter

Branching Tube Branching Tube SpongeSponge

Stove Pipe Stove Pipe SpongeSponge

Vase Vase SpongesSponges

Barrel SpongesBarrel Sponges

Ball Ball SpongesSponges

Rope Rope SpongesSponges

Importance of Sponges

• Reefs provide habitat for many animals

• Vacuums of the sea -- clean up the sea floor/oceans

• Sponges are a commercial venture

• Several medicinal compounds, including antibiotics, antivirual drugs, and drugs for leukemia come from sponges.

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Cool Stuff – Regeneration!

• Tremendous ability to repair and restore lost parts.

• Can also reconstitute selves if totally disintegrated.

• Sponge tissue has some similarity to human connective tissue. Could lead to aid in tissue transplantation.

Embryology

• Weird and different from any other animal.

• Larval stage is usually a flagellated and free swimming. Interior has all cells of sponges but no choanocytes.

• Settles. Creeps around on flagella and eats extracellularly.

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