PHYLUM PORIFERA

Prepared by:JOHN FLORENTINO E. ECHON

G15 0099

The SPONGES

CHARACTERISTICS• Freshwater and marine• Simplest of all animals• Hermaphrodites• Asymmetrical• No systems for repro, digestion,

respiration, sensory, excretion

CHARACTERISTI

CS

CHARACTERISTICS• No true tissues or body

systems of any type• Almost all species are sessile

suspension feeders, larvae free-swimming

• Multicellular• Totipotent cells: like stem cells!

CHARACTERISTI

CS

BODY STRUCTURESpiculescomposed of calcium carbonate or silicon dioxideOften used in sponge ID

BODY

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BODY

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Cells that line surfaces Amoebocytes(archaeocyte)

amoeba-like cells store, digest and

transport food, excrete wastes, secrete skeleton

give rise to buds in asexual reproductionS

BODY

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sclerocytes - secrete spiculesspongocytes - secrete spongincollencyotes - secrete collagen

Cells that line surfacesMesenchyme Beneath the

pinacocytes - a gelatinous protein layer

it contains the skeletal material (ie. spongin and spicules) and amoebocytes

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Cells that line surfacesPinacocytes

outer cells covering sponge; equivalent of epiderm

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Cells that line surfaces Choanocytes-

similar to choanoflagellates

collared cells with flagella - create water current and collect food matter

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Cells that line surfacesPorocytes

Form ostia Cylindrical tube-

like cells Contractile - open

and close pore to regulate diameter

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Sponge Anatomy

Pechenik, 1996

Pinacocyte

Choanocyte

AmoebocytePorocyte

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BODY STRUCTUREBO

DY STRU

CTURE

Body structure/aquiferous system Structural conditions of sponges:

Trend from one large chamber to numerous small chambers. Ascon: one main chamber

(spongocoel) lined with choanocytes

Sycon: choanocyte chambers off the spongocoel

Leucon: has multiple layers of choanocyte chambers

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Syconoid sponges Syconoid: choanoderm folded

Mesohyl two layers thick:

Outer region is cortex (contains skeletal material)

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Asconoid sponges

Asconoid: one-cell thick choanoderm is simple and continuous ~10 cm height Thin walls enclose central cavity;

atrium opens outside via osculum Pinacoderm has specialized cells;

porocytes External opening of porocyte canal

is ostium or incurrent pore

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Leuconoid Sponge

Leuconoid: choanoderm subdivided into separate flagellated chambers

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Types of Spicules4 general types

Monaxon- needle-like or rod-like; straight or curved

Tetraxon- has 4 prongs

Triaxon or Hexaxon- 3 or 6 rayed

Polyaxon- multiple short rods radiating from a common center; burr shaped, star shaped or like a child's jack. Some species have a mixture of types

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TAXANOMY • Taxonomy based on skeletal

elements• Now embryological,

biochemical, histological, and cytological methods to diagnose sponge taxa

TAXON

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Y

Three classes 1. Class Calcarea2. Class Demospongiae3. Class Hexactinellida

TAXON

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Y

Class Calcarea: Calcareous spongesFound in Shallow, tropical water, near shore

Leucetta

Clathrina

Spicules = calcium carbonate

Calcarean spicules lack hollow canals = strong

TAXON

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Y

Leucettusa lancifera Dendy, 1924

TAXON

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YClass Calcarea: Calcareous sponges

Class Hexactinellida (Glass sponges) Silica spicules Spicules join at right angles, sponge appears artificial

TAXON

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Y

Symplectella rowi Dendy, 1924

Class - HexactinellidaTAXO

NO

MY

Euplectella

Class Demospongiae (Demosponges)

Largest and most diverse class of sponges, ~ 90 percent of sponges

Spicules either spongin, an organic substance; or silica, a mineralized substance

Oscarella

TAXON

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Y

Class Demospongiae

Genera Adocia, Halisarca, Myxilla

TAXON

OM

Y

TAXON

OM

YClass Demospongiae

Aciculites pulchra Dendy, 192418

TAXON

OM

YClass Demospongiae

Stelletta crater Dendy, 1924

Spongilla

TAXON

OM

Y

Aquiferous system

Brings water to cells

1 x 10 cm sponge pumps 22.5 l water daily

Large sponge filters body mass every 10-20 s

LIFE PRO

CESSES

Nutrition Carnivorous sponges:

Family Cladorhyzidae! Stalked; tentacle-like

extensions covered with hook-like spicules capture prey

Individual cells engulf and digest prey (intracellular)

Symbionts provide nutrients to some sponges

Methanotrophic bacteria (in some carnivorous sponges!)

Photosynthetic protistsPhoto: Michel Phlibert

LIFE PRO

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Nutrition, Excretion, and Gas Exchange

Intracellular digestion

Continuously circulate water Size selective feeders

Food capture Phagocytosis and pinocytosis

LIFE PRO

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Excretion

Ammonia and gas exchange Diffusion

LIFE PRO

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Most species are sessile as adults Cells frequently move and rearrange

themselves Amoebocytes are highly mobile

One species, Tethya seychellensis, Red Sea, has sticky, filamentous extensions Filaments contract and pull sponge along.

MovementLIFE PRO

CESSES

Sexual Reproduction in Sponges gametes formed by amoebocytes there are both hermaphroditic and dioecious

species most hermaphroditic species produce eggs and

sperm at different times so they do not self fertilize

sperm is released into environment via osculum and is brought in by another sponge via ostia

fertilization takes place in parent sponge zygote is expelled - it drops to bottom and begins

to develop

LIFE PRO

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Reproduction and Development

Sexual process (Demospongiae and Calcarea)

Sperm and oocytes released into environment via aquiferous system

Sperm release -”smoking sponges”

Fertilization in open water (oviparous)

Few viviparous: sperm into nearby sponge’s aquiferous system; sperm to oocyte for fertilization

LIFE PRO

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Reproduction and Development

Madsen sponge releasing sperm

LIFE PRO

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Asexual Reproduction in Sponges

two types: Budding- fragmentation of body wall, buds appear as outgrowth

on sides of spongewhen they reach a certain size they drop off and settle to

bottom to form a new sponge Gemmules- occurs only in freshwater sponges

gemmules are groups of food laden amoebocytes that deposit a hard covering of spicules around them

formation is triggered by environmental conditions such as decreased temperatures

they allow the sponge to pass the winter or periods of drought

after which the outer covering breaks open and a new sponge develops

LIFE PRO

CESSES

LIFE PRO

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ECOLO

GY

Ecology and Importance

Class calcarea: Found primarily shallow water and tropical Class hexatenilleda: Marine, primarily deep water

Ideal habitats for marine animals such as snails, sea stars, sea cucumbers, and shrimp

Mutually beneficial relationships with bacteria, algae and plant-like protists

Many are green due to these organisms living in their tissues

ECOLO

GY

Deep-water sponges provide important habitat to many species of fish and invertebrates, mostly as a source of refuge from predation and adverse conditions (e.g., strong currents) and as focal sites for foraging on prey species that aggregate in sponge habitat.

others likely use sponge habitat as breeding sites.

RELATED

RESEARCHRELATED RESEARCH:

sponges produce a wide variety of bioactive compounds which are widely used in pharmaceuticals: antibiotics, asthma, arthritis,anticancer drugs, chemicals that promotewound healing, anti-inflammatories

eg. antibiotics against bacteria such as E. coli and Staphaureuseg. Acyclovir from Caribbean sponge1st antiviral compound approved for human usefights herpes infections used since 1982

RELATED

RESEARCHRELATED RESEARCH:

Sponges use chemicals to prevent other sponges from growing near them. These chemicals can prevent cancer cells from growing.

One of the first drugs for treating cancer Tectitethya keyensis at Bocas del Toro cancer, cytosinearabinoside, was isolated from the sponge Tectitethya crypta.

RELATED

RESEARCHMarine sponge collagen: isolation,

characterization and effects on the skin parameters surface-pH,

moisture and sebum

Isolation, characterization and molecular weight determination of collagen from marine sponge Spirastrella inconstans (Dendy)