Exercise 36 Flashcards
What are the three common characteristics of all animals?
Eukaryotic
Multicellular
Ingestive feeding heterotrophs
Which phylum is radially symmetric? Asymmetric?
Cnidaria [jellyfish, hydra], Porifera [sponges]
T/F: Cnidarians have true tissues and organs, but poriferans do not.
F. Cnidarians do not really have organs, but they do have tissue.
What does sessile mean, and who is sessile?
Attached, not motile. All poriferans, some cnidarians, especially polyps stages.
Poriferans feed by _______. Most cnidarians feed by _________.
Filter feeding [intracellular digestion], extracellular digestion and intracellular digestion.
What do choanocytes do? What do amoebocytes do? What phylum are they part of?
Draw water in and filter food; many things, they are motile, can digest, and differentiate; Porifera
What is a spicule? A spongocoel?
A crystallin structure that looks like a ninja star. Spongocoel is the large internal cavity in a Grantia.
Name all members of Porifera.
Grantia, Spongia, Euplectella
What is an ostium cell? An osculum?
A cell that helps bring water through to choanocytes. The big open top of a Grantia.
What are spicules made of in
- Grantia
- Euplectella
- Spongia
- crystalline
- silicon
- spongin protein (makes up the flexible skeleton)
Most sponges produce both female and male ______. They can reproduce both _____ and _____.
gametes, sexually, asexually
How many germ layers do Cnidarians have? Worms? What are the names of the layers in cnidarians?
- Endoderm and ectoderm.
Cnidarians don’t have a mesoderm, but they do have a gelatinous _______.
mesoglea
What is polymorphism? Who does it? What morphs does it specialize in?
Having more than one form. Cnidarians. Polyp and medusa.
In cnidarians, ______ hold stinging harpoon structures called _______.
cnidocytes, nematocysts
What is the name for an immature polyp?
A planular larva, or planula.
Name the three Cnidarian classes and tell why they are different.
Hydrozoa: dominant polyp
Scyphozoa: dominant medusa
Anthozoa: only polyp
What are the three species of class Hydrozoa?
Hydra: polyp only, attach to surfaces with basal disk (sometimes even water surface)
Obelia: Colony polyps, but free swimming medusa. Food polyp: gastrozooid [has flagella to catch food], reproduction polyp: gonozooid.
Physalia: Portuguese man of war, strong nematocysts but no cnidocytes, looks like a medusa, but actually is a colony of polymorphic polyps.
What is the species in class Scyphozoa?
Aurelia. Dominant medusa. DOES have cnidocytes. Polyp stage is called a scyphistoma.
Planula looks like a fingerprint
Scyphistoma looks like a torch on fire (tentacles)
Ephyra looks like a flower that isn’t yet mature.
Medusa looks really white and elegant.
What two species are in class Anthozoa?
Metridium: Sea anemone. No medusa. Reproduce by fragmentation of basal disk.
Tubipora: Coral. No medusa. Contains iron salts for color. The whole coral is made of calcium carbonate.
What direction do flagellated canals face? What about incurrent canals?
Inside towards spongocoel. Outside.
