Annelids Flashcards
Phylum Annelida are L..
Lophotrophophores
are annelids coelomates?
yes
define Coelomate
cavity fully lined with peritoneum
lating name for ring?
annulus
defining characteristic of annellida
one of more pairs of chitonous chaetae/ (key-tee)
there are 17,000 species of annelida , true or false?
true
what length can they grow to?
1mm-3m
largest earth worm?
gipsland earthworm
what is the basic annelid organisation?
METAMERISM = THE MAIN BODY IS COMPOSED OF A REGION OF REPEATED UNITS (SEGMENTATION
what are the three parts of the annelida body plan?
- head 2. segmented trunk 3. pygidium
what is the Pygidium
the posterior of the annelid where new segements are created - this is how the worms grow.
define metamerism
the serial repition of segments and organ systems . segments are seperated by septa. segment growth comes from the pygidium
are annelids schizocoelic?
yes
3 advantages of being schizocoelic
- gut seperated from the body wall and with its own musclulature can move independently (can bend without pushing food along inside the gut.
- coelom provides a space where gametes can mature and nutrients and waste products can be moved or stored
- hydrostatic skeleton upon which muscles can act
define hydrostatic skelton
what lines the coelomic cavity?
peritoneum
define mesothelium
an epithelium made of mesoderm
what has the body wall got?
cuticle, epidermis, connective tissue dermis and muscle layer derived from coelomic lining
i toughen up the body wall and resist bulges what am i?
cuticle fibres in the wall
i am bundles of chitonous, thin walled cylinders held together by sclerotinized protein, produced by epithelial cells , what am i?
Chaetae (key-tee)
do annelids have a brain?
they have anterior dorsal brain located in protomium and a ventral pair of longitudinal nerve cords