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Annelida
Nadine Thomas, Elizabeth Skuriat, Julia Woynar,
and Johanna Murray
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Species
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Medium sized phylum with more than 16500 species of
worms
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Freshwater, marine, or terrestrial
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3 Major Classes of Annelida:
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Polychaeta
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Hirudinea
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Oligochaeta
This specimen is an Oligochaeta.
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Characteristics
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Bilaterally symmetrical
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Body has three separate
sections – prostomium, trunk,
and pygidium
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Body has more than two cell
layers, tissues, and organs
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Live in most environments
This specimen is a Polychaeta.
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Characteristics cont’d
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Major invertebrate phylum
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Life span – months to years
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Size – millimeters to meters
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Movement assisted by lobes and bristles
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Ability to regenerate
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Segmentation
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Each organism has segmentation
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Allows movement and protection
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Other phylum with segmentation include Anthropoda and
Chordata
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Segmentation in Annelida can be either external or internal
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Segments separated by septums
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Segments can be used for specialization
This specimen is a leech.
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Biological Systems
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Annelida have a closed circulatory system
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Simple diffusion is used for gas exchange
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Have a digestive system that passes from mouth to anus
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Crop, gizzard, typhosole
Also have a nervous system
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Evolution
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Evolved from the sea
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Oligochaetes developed from polychaete
stock
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Leeches and oligochaetes have clitellum in
common
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Evolution relations between marine to
freshwater.
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References
TEXT
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http://www.earthlife.net/inverts/annelida.html
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http://www.fossilmuseum.net/Tree_of_Life/PhylumAnnelida.htm
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http://www.bu.edu/gk12/eric/Annelida.pdf
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http://www.biosciweb.net/animal/pdf/annel.pdf
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http://www.britannica.com/EBchecked/topic/26308/annelid/31789/Evolution-and-paleontology
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http://www.mhhe.com/biosci/genbio/raven6b/graphics/raven06b/other/raven06_45.pdf
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http://www.biomedcentral.com/1471-2148/9/189
PICTURES
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http://zoologi.snm.ku.dk/english/collections/invertebrates/Collection_databases/Annelida/
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http://www.bio.miami.edu/dana/docs/annelids.html
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http://www.biodiversityexplorer.org/mm/annelids/index.htm
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http://www.cssforum.com.pk/css-optional-subjects/group-d/zoology/14536-notes-zoology-5.html
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