Phulum Porifera Flashcards
(27 cards)
What are Porifera?
The most primitive multicellular organisms with a cellular level of organization (no tissues, organs, or nervous system).
What is the function of ostia in Porifera?
Small openings through which water enters the sponge body.
What is the osculum in Porifera?
The large opening at the top through which water exits.
What is the spongocoel?
The central cavity inside the sponge where water flows through.
What are choanocytes?
Specialized flagellated cells that create water currents and help in filter-feeding.
What supports the skeleton of Porifera?
Spicules (made of calcium carbonate or silica) or spongin fibers.
Are Porifera motile or sessile?
Poriferans are non-motile and attach to rocks or sea floors.
What are the two types of reproduction in Porifera?
Asexual (budding and fragmentation) and sexual (hermaphrodites).
What is the regeneration ability of Porifera?
If a part of the sponge is cut, it can regrow into a new sponge.
How do Porifera perform respiration and excretion?
Both occur through diffusion (no specialized organs).
Name an example of a freshwater sponge.
Spongilla.
What is the habitat of most Porifera?
Primarily marine, though some are freshwater species.
What is the symmetry of Porifera?
Radial or asymmetrical.
What are the main components of the body wall in Porifera?
- Pinacocytes
- Porocytes
- Choanocytes
- Amoebocytes
What are spicules made of?
Calcium carbonate (CaCO₃) or silica (SiO₂).
What is the simplest type of canal system in Porifera?
Asconoid.
What is the most complex canal system in Porifera?
Leuconoid.
What type of feeding do Porifera exhibit?
Filter feeding.
What is intracellular digestion?
Digestion that occurs inside the amoebocytes.
What is the larval stage of Porifera called?
Parenchymula.
What distinguishes Class Calcarea?
Spicules made of calcium carbonate.
What distinguishes Class Hexactinellida?
Spicules made of silica and characterized by a six-pointed symmetry.
What distinguishes Class Demospongiae?
Spicules made of silica or spongin fibers.
What is the ecological importance of Porifera?
- Filter feeders
- Provide habitats for various marine organisms.
