BIO004 - Module 7 Flashcards
Phylum PORIFERA Level of Complexity
Cellular level
made of many cells that perform different functions, but not
organized enough to form tissues
Cellular level
No germ layers despite being metazoan
Phylum PORIFERA
Have free-swimming embryos, but the adults are sessile (attaches on the sea floor)
Phylum PORIFERA
Commensals to aquatic animals (providing shelter and food)
Phylum PORIFERA
means that they have a division of labor to perform specific functions
specialization
different types of cells present in a sponge body
-Choanocyte
-Amoebocyte/Archeocytes
-Sclerocytes
-Spongocytes/Collencyte
-Pinacocytes
“collar cells” because they have a collar of microvilli surrounding a flagellum
choanocyte
The beating of their flagella draws water in like a filter, bringing in oxygen and trapping food
particles between the microvilli
choanocyte
Receive the food particles captured by the
choanocytes and digest them through
phagocytosis
Amoebocyte/Archeocytes
Cells that secrete a support structure called
spicules (made of calcium carbonate or silicone)
Sclerocyte
Cells that secrete a fibrous support structure
called spongin (made of collagen fibers)
Spongocytes/Collencyte
Flat cells that almost forms a true tissue; they are
the cells that forms an outer layer to cover the
sponge (called pinacoderm)
Pinacocytes
pores of the sponges
dermal ostea
3 main designs of canal systems in poriferans
-Asconoid System
-Syconoid System
-Leuconoid System
Choanocytes lie in the walls of a large chamber
Asconoid System
-The simplest organization; the sponge is small and tube shaped
-Found only in Class Calcerae
Asconoid System
Choanocytes lie inside canals
-Syconoid System
-Externally, they look like asconoids,
but with thicker walls
-Found mostly in Class Calcarae,
and some in Class Hexactinellida
Syconoid System
Choanocytes lie in distinct tiny
chambers
Leuconoid System
-The most complex; the tiny
chambers allow sponge to pump
lots of water
-The design allows the sponge to
grow in large sizes
-Mostly found in Class
Demospongiae
Leuconoid System
