Phylum Porifera The Sponges

Porifera Vocabulary 1.Sponge 7.spicule 2.Sessile 8.filter feeding 3.Choanocyte 9.amoebocyte 4.Ostium 10.gemmule 5.Osculum 11.regeneration 6.Spongin 12.hermaphrodite

The Wonderful World of Sponges

Wonderful Sponges Video oTemperature difference @ 300 feet Water became darker & cooler oNO competition oDon’t need as much sunlight oCan grow very large because there is no competition & no need for sun o1 cubic centimeter of sponge can filter 20 L of water (nutrients) per day oEat by filtering “marine snow” ….. Waste and other tiny nutrients oGrow long because they stretch out into the current to try to filter the nutrients

Taxonomy of Porifera Taxonomy Domain – Eukarya Kingdom – Animalia Subkingdom – Parazoa (lacks tissues) Phylum – Porifera (pores) Class – Calcarea Hexactinellida Demospongiae Sclerospongiae Taxonomy of Porifera Taxonomy

General Characteristics Simplest of all animals Lowest level of organized animal life Most are marine

General Characteristics - cont Porifera means pore-bearing (latin) *Aquatic- in water *Marine :saltwater=ocean=high salinity *Freshwater=creeks, lakes = low salinity *salinity-amount of salt

Symmetry Sponges are ASYMMETRICAL (most) Some can be radially symmetrical

Feeding Method Sponges are Filter feeders They feed on plankton (microscopic organisms @ base of food chain)

Water Flow Through the Sponge WATER OUT Water Flow Through the Sponge WATER IN Osculum

Filtering in Sponges

Color the notebook page just as it designated on your worksheet Color the notebook page just as it designated on your worksheet.Use this to color code your worksheet.

Are sponges unicellular or multicellular? Questions Sponges are in what kingdom and phylum? Kingdom____________________ Phylum__________________ Classes____ ___ ___ ___ Are sponges unicellular or multicellular? Are sponges prokaryotes or eukaryotes? What does “Porifera” mean?

Movement Sessile as adults (attach to rocks) Free-swimming larval stage called Dipleurula

Body Cavity/Germ Layers Sponges are acoelomate. Sponges are not made of tissues. They consist of Cells only. The cells are arranged in 2 layers: Outer epidermis Inner endoderm Jelly-like material between cell layers called mesenchyme or mesohyl

Sponge Body Structure Inside body cavity of sponge is hollow Called the Spongocoel Osculum – large opening at the top where excess water leaves

Questions Cont. 5.Name the two body layers of sponges. 6. What type of symmetry do the MAJORITY of sponges have? 7. Why are adult sponges said to be sessile animals?

Specialized Cells - Choanocytes Choanocytes (collar cells) line inside of body cavity (spongocoel) Have flagella that spins to pull in water & food Draw this Collar

Specialized Cells Collar traps plankton (food) from water

Specialized Cells - Amoebocytes Pick up food from choanocytes Finish digestion Move through the mesenchyme & take food to other cells

Questions Cont. 8. What are the 3 jobs of the amoebocyte? 9. What part of a collar cell helps pull in water?

Skeletal Structure of the Sponge Skeleton made of network of protein fibers called Spongin Spicules are hard spear or star-shaped structures

Questions Cont. 10. What two substances give the sponge support? 11. What cells move around in the mesenchyme delivering food and oxygen to other cells?

3 main sponge structures sketch each one on your notes Asconoids (ascon) -Simplest of the sponges - 4 inches or 10 cm -look like a slender sack or tube Syconoids (sycon) -Slightly larger, thicker, and more complex -Holes make rows on a smooth surface -Shaped like tubes. -Sponge wall appears folded Leuconoids (leucon) -Largest of all the sponges -In 5 minutes they filter their own weight in water -Very common body type -More than one osculum is often present

Sponge Reproduction (Asexual) Sponges can regenerate (regrow) lost body parts through mitotic cell division (asexual) Fragmentation Sponges also reproduce asexually by budding.

Sponge Reproduction (Sexual) Sponges are hermaphrodites (produce both eggs & sperm in same organism) Sponges reproduce Sexually by releasing eggs or sperm into the water from the Osculum Cross-fertilize each other’s eggs Sponge releasing eggs & sperm

Sexual Reproduction - Sponges

Adaptations for Survival When conditions are harsh the sponge produces Gemmules. These are buds that contain food, amoebocytes, and a protective covering of spicules When conditions become favorable they will grow into a new sponge.

Taxonomy of Porifera Taxonomy Kingdom – Animalia Subkingdom – Parazoa (lacks tissues) Phylum – Porifera (pores) Class – Calcarea Hexactinellida Demospongiae Sclerospongiae Taxonomy of Porifera Taxonomy

Class Calcarea Calcareous sponges Pastel colors as well as tan and black Spicules made of calcium carbonate Spicules form rays and circles Can be all 3 body types Found in marine and freshwater

Class Hexactinellida Glass sponges Spicules are made of silica Have 6 points and look like stars First group to develop All are marine Syconoid or leuconoid body type

Hexactinellida are special because … Their spicules have electronic “receivers” that respond extremely fast to stimuli Effects are generated across the organism Their tissues are primarily comprised of a primitive liquid, or cytoplasm, known as syncitia While other sponges may alter their structure, hexactinellids are incapable of contracting and constricting their bodies

Class Demospongiae Horn sponges / bath sponges Largest class (90% of sponges) Spicules are made of spongin, silica or mixture of both Many diverse orders, including all large sponges Includes all commercial species Mostly marine Leuconoid body form

Class Sclerospongiae Coralline sponges Internal skeleton of siliceous spicules and spongin plus an outer encasement of calcium carbonate The layered skeletons look similar to reef corals – (hence the common name) All marine Few modern species

Why is there question about the validity of Class Sclerospongiae?     The class Sclerospongiae has been subjected to change as new scientific innovations and theories have developed.  Many scientists, including those who conferred with us, dispute over the controversial existence of the Sclerospongiae class.  New research suggests that particular integral components of this class promote the fact that its members may be distributed among the classes of the Demospongiae and Calcarea. 

A Gemmule

Branching Tube Sponge

Stove Pipe Sponge

Vase Sponges

Barrel Sponges

Ball Sponges

Rope Sponges

Economic Importance Sponges can be harvested in large amounts to be used as a “sponge ”! There are environmental concerns over this and synthetic sponges are also made.

Questions 12.Identify and differentiate the 3 main sponge structures. 13. How do sponges reproduce asexually? 14. How do sponges reproduce sexually? 15. What does it mean to be a hermaphrodite? 16. What is the function of gemmules?