PHYLUM PORIFERA COMMON NAME: SPONGES There are 900 species in this group - mostly marine . Below are several examples. Yellow sponge Vase sponge Tube sponge
Dec 28, 2015
PHYLUM PORIFERACOMMON NAME: SPONGES
There are 900 species in this group - mostly marine .
Below are several examples.
Yellow sponge Vase
spongeTube sponge
Key Characteristics of Sponges
multicellular with few specialized cells (no mouth, tissues, or organ systems)
asymmetrical- no front/back or left/right sides
simple skeleton: Harder sponges: skeleton is
made of spiny spicules Softer sponges: skeleton is
made of spongin, a network of flexible protein fibers. harvested and used as natural
bath sponges.
Natural bath sponge
Barrel SpongeKingdom
: Animalia
Phylum: Porifera
Class:Demospongiae
Order: Haplosclerida
Family: Petrosiidae
Genus: Xestospongia
Species:X. testudinari
Feeding
Fundamental question: How do choanocytes help sponges feed? specialized cells with flagella move a steady current of water (and food!)
through the sponge. Note: also helps bring oxygen & carry away waste
Filter feeders: sifting microscopic food particles from the water.
Respiration, Circulation, Excretion
As water moves through the body cavity, oxygen dissolved in the water diffuses into the cells of the sponge.
At the same time, waste such as carbon dioxide and ammonia diffuse into the water and are carried away.
Water flow brings oxygen and carries away wastes
Response
Very limited… no nervous system.
Many sponges protect themselves by producing toxins that make them poisonous to potential predators.
Toxic Poison Finger Sponge- note the aposematic coloration!
ReproductionSexual reproduction Hermaphrodites:
produce both egg and sperm, but at different times.
Asexual reproductionSome sponges can reproduce by a process called budding.
EcologySPONGES… provide habitat for marine animals -
snails, sea stars and shrimp
are a food source for many organisms such as sea stars and fishes.
Mutualistic symbiosis: provide a protected place for bacteria, algae and plantlike protists to grow. These photosynthetic organisms provide food
and oxygen to the sponge.
Small fish can hide inside sponges
Threatened species: Cloud Sponge
-They are extremely fragile… bodies are composed of silica (glass)
Bottom trawling breaks their bodies- threatening the survival of the population
Threatened cloud sponge
Resources
Miller, Kenneth and Levine, Joseph. Biology. Upper Saddle River: Prentice Hall, 2004.
"Marine Mysteries - Could Solving These Mysteries Save The Oceans?" Marine Mysteries. World Wildlife Federation, n.d. Web. 11 June 2012. <http://www.marinemysteries.ca/>.
"Treasures of the Sea Exhibit." Treasures of the Sea. Delaware Technical Community College, n.d. Web. 11 June 2012. <http://www.treasuresofthesea.org/>.