Animals, multicellular, heterotrophic, no cell walls, few specialized cells
Choanocytes (specialized cells use flagella to move current of water thru sponge, trap
Osculum (large hole at top)
Spicule (made of calcium carbonate or silica; makes skeleton of hard sponges, captures
sunlight and directs the sunlight to cells below surface of cells, these cells
Archaeocytes (specialized cells that move around within the walls of the sponge,
complete digestive process, carry sperm to egg, groups of archaeocytes covered by
spicules are called
The movement of water thru sponge is key for feeding (intracellular), reproduction
internal fertilization – eggs fertilized in body, zygote develops called larvae
which are motile, asexually
budding, part of sponge breaks off and grows/ or it
produce gemmules, which later become a new sponge ), circulation, excretion, response
(no nervous systems, produce toxins)
Commensalism relationships w/ photo bacteria, algae, plant protists, which provide O2
and sponge provides shelter.
Soft-bodies, carnivorous animals, have stinging tentacles around their mouths, simplest
animals that have symmetry and specialized tissues.
Cnidocytes (stinging cells for defense, captures prey, contains nematocyst)
Nematocyst( poison filled stinging dart, paralyzes prey)
Two life stages:
polyp(cylindrical body with armlike tentacles, upwards mouth, sessile).
Medusa (motile, bell-shaped, downwards mouth).
Three main tissues in both stages: epidermis, mesolgea, gastroderm (lines gastrovascular
cavity- digestive chamber with one opening)
Response (nerve net- loosely organized network of nerve cells, allow cnidarians to detect
Statocysts- sensory cells detect gravity, have
Oceli which detect light.
Hydrostatic skeleton (layer of circular muscles and longitudinal muscles; movement
Reproduction: external fertilization outside females body, zygote grows into larva, larva
attaches to a hard surface and develops into polyp, poly release medusa
Jellyfish: Scyphozoa, no colonies, sexual reproduction, medusas, can grow huge
Hydras and relatives: hydrozoa, colonies, Portuguese man of war contains specialized
polyps, hydras: solitary polyps only, get nutrition from stinging small prey and symbiotic
Sea anemones: anthozoa, solitary polyps
. Corals: colonial, single polyp first grows when
motile larva settles, new polyps grows thru budding, sexual reproduction, require light for
Chemicals, divers, sediments cause stress and kill corals by poisoning, damaging, or
Coral bleaching occurs with high temps in the water, and produces
.. because of global warming.