Unit 2: Lesson 10- Sponges & Jellyfish Flashcards
Animal
Eukaryote, multicellular, has nerve and muscle cells, no cell walls, chemoheterotrophs, diploid-dominant, mostly sexual
Radial vs Bilateral
Radial have more area to “interact” with the world.
Bilateral have better directional movement.
What gave rise to animals?
Choanoflagellates
Development
Zygote, Morula, Blastula, Gastrula
Tissues
Ectoderm- outer tissue
Mesoderm- middle tissue
Endoderm- inner tissue
Diploblastic vs Triploblastic
Diploblastic- radial symmetry, lack mesoderm
Triploblastic- bilateral symmetry
Coelom
Internal body cavity with no outside opening.
- Acoelomate- no coelom (jellyfish, flatworms)
- Pseudocoelomate- “false coelom” partially surrounded by mesoderm
- Coelomate- Fully surrounded by mesoderm
Protostome
Spiral cleavage of division
Determinate- cells specialize early
Mesoderm develops independently from archenteron
Mouth forms first
Deuterostome
Radial cleavage of division
Indeterminate- cells undifferentiated until gastrulation
Mesoderm buds from archenteron
Anus forms first
Phylum Porifera
Sponges, radial symmetry, no gastrulation (so no true tissues)
Phylum Porifera Characteristics
Choanocytes. amoebocytes, spicules
Phylum Porifera Body Forms
Asconoid- direct pores go to central opening, thin wall, clear osculum.
Syconoid- Chambers of choanocytes in pores, thick walls, clear osculum
Leuconoid- Thick walls, unclear osculum
Sponge Life Cycle
Male sponge produces sperm that fertilizes a female, producing a free living larva that becomes a sponge.
Phylum Cnidaria
Jellies, corals, anemones, hydras, radial symmetry, diploblastic, acoelomate, “closed gut”/gastro-vascular cavity
Phylum Cnidaria characteristics
Alternate between polyp (sessile) and medusa (free-swimming), predators, stinging cells (nematocysts)
Jellyfish Stingers
Nematocyst is a stinger coiled in a capsule, a hypotonic environment will cause the capsule to burst and release venom.
Class Hydrozoa (Phylum Cnidaria)
Polyp dominant, have feeding polyps and reproductive polyps. Man o’ War is made of different species.
Class Hydrozoa (Phylum Cnidaria) Life Cycle
A reproductive polyp releases small medusa that undergo meiosis and produce eggs or sperm which fertilize and make a zygote/planula, which anchors, and becomes an adult polyp.
Class Scyphozoa (Phylum Cnidaria)
Jellyfish, medusa-dominant
Class Cubozoa (Phylum Cnidaria)
Box jellyfish, highly venomous
Class Anthozoa (Phylum Cnidaria)
Corals, anemones, polyp-dominant, mutualistic (corals have a (CaCO3) skeleton for zooxanthallae, anemones have clownfish)
Class Ctenophora (Phylum Cnidaria)
Comb jellies, 8 rows of cilia, tentacles have colloblasts (sticky cells), bioluminescent
