Lecture 10: Animal Diversity 2 Flashcards
Phylum Cnidaria aka
“nettle animals”
What are the different group of Cnidaria?
1) Anthozoa
2) Schyfozoa
3) Staurozoa
4) Cubozoa
5) Hydrozoa
*Cnidaria mainly refers to corals and jellyfish
Anthozoa
Corals and sea anemones
Schyfozoa
swimming jellyfish
Staurozoa
stalked jellyfish
Cubozoa
Box jellyfish
Hydrozoa
Hydroids and siphonophores
Two basic body forms of Cnidaria
- the polyp (sedentary)
- the medusa (mobile)
Note: Many have both forms in their life cycle
What is the main adaptation for feeding and defense for Cnidaria?
Nematocysts: organelle that functions like a miniature harpoon
Nematocysts
organelle that functions like a miniature harpoon
Explain the process of Nematocysts
1) Trigger senses ‘foreign’ chemical profile
2) ‘Harpoon’ released - can pierce a crab shell
3) Releases toxin - some species have toxins fatal to humans
What do Cnidarians use their nematocysts for?
1) Capturing prey
2) Defense against predators
3) Defending territories
Corals
-polyp-form cnidarians, live in large colonies, and secrete calcium carbonate
When old polyps die,
new ones build on top
Coral Reefs
millions of coral skeletons with living corals on the periphery
Reefs are important because…
1) provide habitat
2) protect coast lines from storms
3) sequester carbon
4) fix nitrogen
5) filter water
6) provide nutrients to marine life
Corals live in…
shallow, clear, saline water because they are getting their energy thru photosynthesis
Corals get much of their energy and carbon from…
photosynthesizing protists called dinoflagellates that live within their cells
Dinoflagellates are…
-the “autotrophs” (self- feeders) of the coral reef community
What is a good indicator of water quality?
Corals (ph balance)
What are the two types of Cnidaria Reproduction?
- Asexual reproduction
- Sexual reproduction
cnidaria Asexual reproduction
budding off from polyps
Cnidaria Sexual reproduction
fertilized eggs give rise to mobile, planktonic forms (plankton: marine drifters)
How do Lophotrochozoans grow?
incrementally by adding to their skeletal elements (ie - Clame)