Marine Invertebrate Zoology

Transcription

1 Marine Invertebrate Zoology Invertebrate Classification and 1

2 The Meek Will Inherit the Earth

3 Why Study Invertebrates? 3 Many diseases that effect humans and the animals we depend on are caused by invertebrates Invertebrates are the base of most food webs Invertebrates are the base of many medical studies: Control of gene expression Aging, cell death, fertilization and chemoreception Transmission of nerve impulses, biochemical basis of learning and memory Genetic basis for the predisposition for major diseases (i.e. type II diabetes) Isolating unique chemicals for biomedical reasons Using invertebrates as indicators in monitoring aquatic systems for pollutants

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5 Invertebrate Classification and Classification by cell #, and body symmetry Classification by developmental pattern Classification by evolutionary relationship Methods used in deducing evolutionary relationships Classification by habitat and lifestyle 5

6 Classification by Cell #, and Body Symmetry Cell Number Metazoans Unicellular Body Symmetry Asymmetrical Bilateral Radial 6

7 Classification by Developmental Pattern Multicellular animals have been divided into two groups based on the # of germ layers Germ layer Diploblastic Ectoderm Endoderm Triploblastic Mesoderm Most metazoans are triploblastic 7

8 Classification by Developmental Pattern Triploblastic animals can be classified even further Acoelomate Pseudocoelomate 8 Coelomate

9 Different Developmental Types Triploblastic Acoelomate Pseudocoelomate Coelomates Protostomes Deutrostomes 9

10 Advantages of the Coelom The digestive system is independent of the body wall and locomotory activities Room for the gut, gonads, and embryo s to bulge Fluid in coelom can distribute oxygen, nutrients and hormones through the body Fluid filled coelom leads to more effective locomotory systems 10

11 Classification by Evolutionary Relationship By far the most familiar is the frame work created 250 years ago by Linnaeus Organisms grouped in a taxon show a high degree of similarity Kingdom Family Phylum Class Genus Species Binomial nomenclature 11 Order

12 Deducing Evolutionary How do we compile evolutionary relationships? PCR (polymerase chain reaction) In what ways are evolutionary relationships depicted? Cladograms 12

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14 Classification by Habitat and Lifestyle 14 Terrestrial, marine, or aquatic Intertidal or subtidal Mobile, sessile, or sedentary, planktonic Herbivores, carnivores, suspension feeders, deposit feeders, filter feeders Symbiotic associations Ectosymbionts Endosymbionts Mutualism, commensalism, parasitism

15 Classification 15 The 5 Kingdoms we use today. Monera: single celled, prokaryote organisms Cyanobacteria (blue-green algae) Protista: single celled, contains nucleus and internal subdivisions Diatoms, dinoflagellates, and protozoans Fungi: multicellular, no photosynthesis, nutrition by absorption Mushrooms Plantae: multicellular, autotrophs Animalia: multicellular, heterotrophs

16 Multiple Kingdom and Domain Classification