 Sponges- Porifera
 Jellyfish, Hydroids, Corals, Sea Anemones – Cnidaria
 Comb Jellies- Ctenophora
 Chitons, Snails, Bivalves, Octopi, Squid, Nautilus,




Nudibranchs, Cuttlefish- Mollusca
- Sea Spider, Crabs, Shrimp, Krill, Amphipods,
Copepods, Barnacles- Arthropods
- Sea Stars, Ophiuroids, Sea Urchins, Sea Cucumbers,
Crinoids- Echinodermata
- Tunicates and Lancelets- Hemichordates
- Marine Worms
 Considered an animal
 Simplest of all animals with many specialized cells
 Asymmetrical – no symmetry
 Variety of shapes and colors
 Evolved from a single celled Eukaryotic
(Protistans)
 Loose aggregation of cells.
 Shapes may be determined by the shape of the
sediment and water currents flowing by them.
 Calcarea are chalky sponges with calcium
carbonate spicules
 Hexactinella includes glass sponges & the
Venus flower basket with silica spicules
 Demospongiae include horny & bath
sponges with only spongin or spongin &
silica spicules
 Sclerospongiae are coral sponges & have
spongin & silica and calcium carbonate
spicule
 Built around a system of water canals.
 Body is full of tiny holes called pores or
ostia, where large amounts of water circulate
nutrients, oxygen, and remove waste.
 Water enters through the ostia -> carried to
the spacious cavity called the spongocoel ->
water then exits the spongocoel through a
large opening called the osculum.
 Collar cells or choanocytes have a
flagellum and when they all move it
creates a great force which then moves
the water through the sponge.
 Pinacocytes-> layer of cells that provide
an outer covering for the sponge, lines
the internal chambers.
 Archaeocytes->
 resemble amoebas
 move throughout the sponges body
 can form into any cell
 important in repair and regeneration
 transport food
 Spicules->
 Skeletal elements that give support to sponge’s
body
 Made up of calcium carbonate, silica, or sponging
(protein that allows the sponge to be flexible).
 Three different types
 The folded body has evolved to overcome
the problem of water flow and surface area.
The increased folds increase the surface area
of the collar cells and reduce the
spongocoel, which decreases the amount of
water needed to be circulated. In the end it
results in increased water flow and
increased sponge growth.
Asconoid
Syconoid
 Simplest form  First stages
 Clusters
of body wall
 Tubular /
folding
Small
 Internal
 As it grows
pockets of
the
collar cells.
spongocoel
increases.
Leuconoid
 Highest
degree of
folding
 Largest
sponges
 Pumps 5
gallons of
water per
day.
 Feed on bacteria, plankton, and
detritus
 Suspension feeders-> feed on
material that swims by.
 Filter feeders-> filter food from the
water.
 Food is engulfed and digested by
pinacocytes and archaeocytes along the
canal system-> carry them-> 80% of the
food gets trapped by the collar cells->
flagellum strains the food by the current
created by the beating tails-> draws water in
through the ostia and expels it through the
osculum.
 Sexual and asexual
 Budding-> not common. Groups of cells on
the outer surface of the sponge develop and
grow into tiny new sponges. When it gets to
a certain size the sponge drops off and either
floats away or establishes itself near the
parent.
 Fragmentation-> production of new cells
that have been broken off by waves, storms,
or predators.
 Hermaphrodites- produce both male and female
gametes.
 Sperm cells- form from modified collar cells
 Eggs- archaeocytes / collar cells
 The stimulus that initiates the production of gametes =
change in water temperature (photoperiod= amount of
light / dark in 24 hours)
 Sperm cells-> enters-> engulfed by collar cells-> both
lose flagella-> collar cell transports sperm to the egg.
 Amphiblastula- larval stage-> water column-> adult
sponge 
 Biggest problem- finding a suitable place to attach. They





compete with corals and bryozoans. Some produce
chemicals that kill corals or inhibit growth
Boring Sponge – bores into corals and dead shells
Crabs use pieces of sponge as camouflage -> sponge
grows on the crabs shell
Most are toxic to fish- few predators
Sea turtles eat them yummy  Hawksbill
Symbiotic relationships:
 Mutualism- cyanobacteria-> food / nutrients / protection
 Commensalism- shrimp hide out in there until they are too big
 http://www.youtube.com/watch?v=BW05vMziy2o
 http://www.youtube.com/watch?v=T7E1rq7zHLc
 http://www.youtube.com/watch?v=KOFFzXNYJG0
 http://www.youtube.com/watch?v=mVavqt4Sbyo