Phylum- Porifera
GENERAL CHARACTERS:
The phylum porifera meaning pore bearing animals. The term is coined from Latin –Porous –pore ferre- to bear . The body surface bears pores.General characters.
1. They are aquatic animals found in fresh water some are marine forms.
2. They are diploblastic, multicellular animals
3. The consist of outer ectoderm and inner endoderm.
4. Between ectoderm and endoderm gelatinous mesogloea is present.
5. Mesogloea contains different types of amoeboid cells.
6. The shape of body is vas shaped or cylindrical, symmetrical or asymmetrical.
7. The surface of body shows minute pores called ostia.
8. Toward the free end large opening is present called osculum.
9. The body cavity encloses large cavity called spongocoel.
10. Canal system is well developed consists of incurrent canal, excurrent canals.
11. Body is supported by calcareous or silicic spicules and spongin fiber.
12. Digestion is holozoic and intracellular.
13. Reproduction is sexual as well as asexual.
14. Regeneration power is very high.
15. Fertilization is internal.
16. Cleavage is holoblastic.
Phylum porifera consists of three classes these are
1. Class 1 - Calcaria
2. Class 2 – Desmospongia
3. Class 3 –Hexactinellida
SYCON
Kingdome- Anemalia Eukaryotic, Multi-cellular, without
chloroplast
Phylum
- Porifera Pore bearing, cellular grade organization.
Class
– Calcaria Exoskeleton is made up of calcium carbonate,
Order
– Heterocoela Canal system is well developed.
Type
– Schypha/Sycon
CHARACTERS:
- Sycon is solitary or colonial sponge found attached to rock or any solid substratum.
- Body is made up of many cylinders attached at the base.
- Exoskeleton is made up of calcium carbonate.
- Each cylinder show wide opening called osculum.
- Body surface is perforated with minute aperture called ostia.
- Sycon encloses large cavity called as spongocoel.
- Canal system is well developed.
HYALONEMA
Kingdome-
Anemalia Eukaryotic,
Multi-cellular, without chloroplast
Phylum
- Porifera Pore
bearing, cellular grade organization.
Class
– Calcaria Exoskeleton
is made up of calcium carbonate,
Order
– Amhidiscophora Spicule
are ambhidisc i.e. with convex disc
Type
– Hylonema (Glassroap)
- Reproduction sexually as well as asexually. Asexual reproduction by budding and regeneration.
CHARACTERS:
- It is commonly called as glassrope sponge
- Body is rounded or oval and radially symmetrical.
- Five and six rayed spicule extends from all over the body.
- Spicules are amphidisc i.e. with convex disc.
- Attaché to substratum by stalk like root tuft..
- Ex-current canal opens on gastral surface.
- Presence of gastral cone.
SPONGILLA
Phylum - Porifera Pore
bearing, cellular grade organization.
Class - Demospongia Spongin
fibres or siliceous spicules present. Canal system is present.
Order - Monaxonida
Spongin may or may not be
present, spicules monaxon type.
Type - Spongilla
CHARACTERS:
- Spongilla also called as bath sponge .
- Spongilla is freshwater colonial sponge found in ponds and lake.
- It found attached to the submerged objects.
- It is brown in colour.
- Spongilla show wide opening called osculum.
- Body surface is perforated with minute aperture called ostia.
- Body surface shows presence of minute apertures called ostia.
- The skeleton shows spongin fibers and spicules.
- Reproduction sexually as well as asexually
Dr, Vidhin Kamble
Department of Zoology
Sangola College, Sangola
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