Summary Overview phyla+classes

Phyla/Classes

, PHYLA

Porifera


Metazoa (animal)

- Aquatic
- Sessile (can’t self-locomote)
o Flagella to create a water current within the spongocoel
o Collar to catch food within the spongocoel
- Multicellular, asymmetric body plan, diploblastic
- Aggregation of cell types, only little integration of functions (no tissues)
o Amoebocyte  Mobile cell that plays a role in defense & food uptake
o Choanocyte  Cells that line the interior of sponge cells, they generate a water current
o Porocyte  Tubular cells that make up the pores of the sponge
o Pinacocyte  Flat cells found on the outermost layer of the sponge
- Body with pores, canals and chambers
o Spongocoel
- “Skeletal structure” of collagen, spongin and spicules
- No true tissue
- 3 different types of sponges: Asconoid type – Leucosolenia
Syconoid type – Grantia
Leuconoid type – Halichondria panacea

, Cnidaria


Metazoa (animal)  Eumetazoa (with true tissue)  Radiata (radially symmetrical)

- Most species are marine
o Free-living medusa (or jellyfish)
o Sessile polyp
- Radially symmetrical
- Eumetozoan, diploblastic (epidermis and gastrodermis, separated by mesoglea)
- Distinctive cell type  cnidocyte
o In cnidocytes, nematocysts can be triggered to shoot a organelle that contains toxin
- Carnivorous
o Tentacles used to catch prey
- Thecata
o Disk-shaped when medusa
o Often forms colonies
 Hydranth  feeding polyp
 Gonangium  reproductive polyp
- Athecata
o Bell-shaped when medusa
- Extracellular digestion in gastrovascular cavity