Exam 1 - Porifera Flashcards
(25 cards)
What does Porifera mean?
pore-bearing
Are Porifera symmetrical or asymmetrical?
asymmetrical
Are Porifera classified as plants or animals?
now classified as animals, but used to be classified as plants.
True or false: Porifera are the longest surviving animals on Earth.
True.
Cellular structure
no organs or tissues, but they do have different layers of tissues.
Where are Porifera found?
mostly marine with one family of freshwater, wide range of depths because no need for sunlight, and they are sessile.
What is the atrium/spongocoel of a Porifera?
the internal cavity.
How do Porifera pump water?
drawn in through porocytes in the body wall and then pumps it back out through the osculum.
What are choanocytes?
cells with flagella that cause the water flow and trap food particles that are suspended in the water.
What are amebocytes?
cells that move through the body with different functions.
How do Porifera exchange gases, remove wastes, and release gametes?
through the water flow.
What are archaeocytes?
amoeboid cells that phagocytize food particles and form other cells that produce spicules and gametes.
What is the mesohyl?
found in the gelatinous layer in the middle of the sponge and contains skeleton composed of spicules.
What is the function of spicules?
support and protection.
How are sponges classified?
by type of spicules and complexity of ell arrangement.
How do sponges reproduce?
asexually: fragmenting/budding
sexually: sperm leaves through osculum and enters another sponge through water currents. Fertilized eggs develop into ciliated, free-swimming larvae.
What are asconoid sponges?
simple vase-like structure with limitations on size.
What are synconoid sponges?
choanocyte layer is folded, single osculum, complex body wall, and can increase in size.
How do synconoid sponges get water to the spongocoel?
water is received through incurrent canals, then goes to radial canals, then to the spongocoel.
What are leuconoid sponges?
no atrium, several chambers with choanocytes, series of incurrent canals leading to chambers, water exits through excurrent canals, and significant increase in surface area.
What is class calcarea?
spicules composed of calcium carbonate, greatest diversity in tropics, primarily in shallow waters.
What is class hexactinellida?
glass sponges, siliceous spicules, early branch within Porifera.
What is class demospongidae?
> 90% of known species are in this class, composed of spongin fibers and/or siliceous spicules, all members are leuconoids.
What happened in Tarpon Springs, FL?
was sponge capital competing with Greece until a red tide outbreak in 1946 wiped out sponge beds. When the synthetic sponge was introduced, it virtually eliminated the FL sponging industry.
