plankton organisms that drift with the currents. zooplankton animal plankton – many different...
Post on 22-Dec-2015
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Zooplankton
• Meroplankton– Only found in plankton for part of their life
cycle– Larvae of benthic adults
Invertebrates
• Animals without backbones
• No internal rigid skeleton
• Softbodied
• Many have hard external coverings
Phylum Mollusca
• 3 Main groups– Gastropods - snails– Bivalves- oysters, clams, mussels– Cephalopods – octopuses, squids
Gastropods
• Spiral shells
• Shell-less = sea slugs or nudibranchs
• Project head and muscular foot when moving
Cephalopods
• Largest of the invertebrates (59 ft squid)
• Foot modified into tentacles
• Active predators
• Highly evolved nervous system