Poriferans
the simplest invertebrates
Choanocytes
defining cell type of poriferans
Sponges
most familiar organisms
Sponges
Their body structure facilitates the movement of water for feeding, excretion, and gas exchange.
Reproduce by sexual as well as asexual methods
Hermaphroditic
possess both male and female gametes
Ostia
Pores on the side that allow water to flow into the spongocoel
Osculum
Large opening where water exits after passing through the spongocoel
Spongocoel
Large Central cavity lined with chondrocytes and other cells
Calcarea
has calcareous spicules
Hexactinelida
with six-rayed siliceous spicule
Demospongiae
have siliceous spicules, spongin or both
Coraline
sponges have multilayered calcium carbonate skeletons
Cnidarians
exhibit radial or biradial symmetry
cnidocytes
defining cell type of cnidarians
stinging cells
serve to capture prey or repel predators.
Gastrovascular activity
serves both digestive and circulatory functions with gas exchange by diffusion between cells and the environment.
Hydranth
oral end of the polyp bearing the mouth and tentacles
Polyp and Medusa
2 types of body forms of Cnidarians
Basal disc
used for attachment to a substrate
Hypostome
conical elevation containing the mouth part
Bud
asexually produced outgrowth
pedalia
Cubozoa contain muscular Pads called
Scyphozoa
true jelly fish
Cubozoa
boxy jellyfish
Anthozoa
exhibit a sessile polyp body plan only ▪ all marine dwelling ▪ may be colonial or solitary