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4 Cards in this Set
- Front
- Back
- 3rd side (hint)
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PHYLUM PORIFERA: SPONGE, THE POROUS ANIMAL |
Sponges belong to Phylum Porifera (L. porus, pore, + fera, bearing)
- filter-feeding system adequate for their inactive life habit
- unique canal systems
- with varying sizes - many are brightly colored because of pigments in dermal cells |
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CHARACTERISTICS OF PHYLUM PORIFERA |
- Multicellular, body is a loose aggregation of cells
- Body with pores called ostia and osculum
- Canals and chambers
- All are aquatic, mostly marine
- Radial symmetry or none
- Has flat pinacocytes
- flagellated collar cells called choanocytes
- gelatinous protein matrix called mesohyl/mesoglea that contains amebocytes |
explanation (1st bullet) - sponges have a simpler structure where cells work together for basic functions, like filtering water and capturing food particles.
Pinacocytes - which cover their bodies like a layer of skin
Choanocytes - special cells with tiny whip-like tails that help move water and capture food.
Mesohyl or Mesoglea - a gel layer holding everything together and filled with amebocytes (carrying nutrients and repairing the sponge) |
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CHARACTERISTICS OF PHYLUM PORIFERA |
- Skeletal structure is made of a protein and calcareous (calcium) or siliceous (silica) crystalline spicules
- It is often combined with variously modified collagen called spongin
- No organs or true tissues
- Digestion is intracellular
- Excretion (getting rid of waste) and respiration (breathing or exchanging gases) are by diffusion |
Spongin - is like a special, flexible glue or binder that holds the crystalline spicules and the protein framework together in the sponge's skeleton. This combination provides both structure and flexibility to the sponge's body.
explanation to the 4th bullet - sponges perform digestion inside their cells, a process that helps them obtain nutrients from the water they filter.
Diffusion - waste materials are let out, and oxygen is taken in by allowing tiny particles to move in and out of their cells naturally. This simple method helps sponges stay clean and get the oxygen they need. |
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CHARACTERISTICS OF PHYLUM PORIFERA |
- Reactions to stimuli are local and independent
- All adults are sessile and attached to substratum
- Asexual reproduction is by budding or gemmule formation
- Sexual reproduction Class Demospongiae – marineClass Demospongiae – freshwaterClass CalcareaClass Hexactinellida |
explanation of the 1st bullet: when something triggers a response in one part of the sponge, it doesn't necessarily affect the entire sponge. Sessile - which means they are permanently attached to a surface or substrate. They don't move around like animals that can walk or swim. |
