which are in the phylum Porifera, have no symmetry and a cellular
level of organization. They are all sessile and may be encrusting
or grow upright. Sponges are filter feeders and actively trap food
particles that are swept into their body cavities. Different species
of sponges have different support systems. Some have tiny starburst-shaped
spicules made of silica (glass) embedded in their bodies; some have
spicules made of calcium carbonate. Other species have a thick,
rubbery support system made up of a protein called spongin. Some
sponges have both spicules and spongin, some have only one or the
other, and some have neither.
the links below to learn more about different sponges that are found in
the intertidal of the Gulf of California. To go back to the Gallery of
Marine Life, click here.
a practice quiz on the Phylum Porifera, click here.