what are common names for annelida?
segmented worms
around when did the annelida evolve?
around 500 million years ago
what type of symmetry does annelida have?
bilateral symmetry
are annelida segmented?
yes
do annelida have tissues?
yes
do annelida have a coelom?
yes
what are longitudinal muscles?
muscles that run up and down the body to shorten segments that aid in movement
what are circular muscles?
they surround the longitudinal muscles that lengthen muscles when contracted to aid in movement
what are setae?
bristles found on the ventral surface of the earthworm, used for traction and movement.
what is clitellum?
segments that secrete a mucus ring with reproductive cells
what are septa?
the tissue that separates segments
how do annelida move around?
my contracting their muscles to move the organism in an accordion-like manner
how do annelids get their nutrients?
by preying on small invertebrates or through filtering decomposing matter
how do segmented worms reproduce asexually?
the clitellum creates a mucus ring where an egg and sperm cell is created. then the egg is fertilized in the mucus ring and put into the soil to hatch
how do segmented worms reproduce sexually?
the clitellum creates a mucus ring where the egg or sperm is produced and then another worm rubs bodies with the worm to fertilize the egg
what makes up the annelida digestive system?
the mouth, pharynx, esophagus, crop, gizzard, intestines, and anus
what are the three classes of annelids?
oligochate, polychaets, and hirudinea
what are oligochates(earthworms) and where do they live?
the class of annelids that means “few bristles” because of the setae bristles that are used to move. they live in the soil
what are polychaets and where do they live?
they mean “many bristles” and live in the ocean. ex. plume worms, bristle worms, and sand worms
what are hirudinea?
they are part-time parasites with suckers on both sides of their bodies. they are found in ocean sands and reefs ex. leeches
how many species of annelids are there?
around 9000 species
how many hearts do annelids have?
5 hearts
how many germ layers do annelids have?
three germ layers, triploblastic
annelida are the first…
coelumates