BIOL 2003 Lecture Notes - Lecture 5: Radula, Odontophore, Nacre
31 Aug 2016
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Document Summary
Phylum cycliophora - only on the mouthparts of certain lobsters. Look like bryozoans, but anus on the inside of tentacles. Look like hydroid cnidarians but have ciliated tentacles (and are triploblasts) Extremely diverse (85,000+ species) and disparate (8 classes) Most are small (<10 cm) but are also some of the biggest invertebrates. Human importance: food (calamari, escargot, mussels, scallops, clams , pearls and shells (cowries = currency, bio-indicators (ex. Zebra mussels, oysters - environmental indicators and filters: pests (bites, stings, crops, parasites, fouling, biotechno importance (nerve cells and axons; shell strength) Mollusc (= soft animal) are mollusc because: visceral mass - everything that is living inside of it (now includes mantle/mantle cavity) Contains internal organs - digestive, excretory, reproductive and respiratory. Made by the outer layer of the mantle. Periostracum = outer organic layer (resistant protein conchiolin) Nacre = continuously grows and thickens; calcium carbonate + protein sheets; inner layer. Excretion (metabolic and digestive), respiratory, reproduction: head-foot.
