Worms

Acoelomate
an invertebrate lacking a coelom
cephalization
a tendency in the evolution of organisms to concentrate the sensory and neural organs in an anterior head
pharyngeal sheath
Opens externally toward posterior region of organism and can be extended through oral opening
flame cells
is a specialized excretory cell found in the simplest freshwater invertebrates, including flatworms
nephridia
is an invertebrate organ which occurs in pairs and function similar to kidneys
ocelli
A small simple eye, found in many invertebrates
cirrus
are a genus of atmospheric clouds generally characterized by thin, wispy strands
trematoda
is a class within the phylum Platyhelminthes that contains two groups of parasitic flatworms, commonly referred to as “flukes”
sporocyst
is a common name of a lifecycle stage in two unrelated groups of species
sucker (oral, ventral)
an anterior oral sucker surrounding the mouth
cestoda
For the early name for a computer “worm”, see Computer worm
proglottid
Each segment in the strobila of a tapeworm, containing a complete sexually mature reproductive system
nemertea
is a phylum of invertebrate animals also known as “ribbon worms” or “proboscis worms”
proboscis
is an elongated appendage from the head of an animal, either a vertebrate or an invertebrate
pseudocoelomate
any of a group of invertebrates with a three-layered body that has a fluid-filled body cavity (pseudocoelom) between the endoderm and the mesoderm (the innermost and middle tissue layers)
nematoda
are bilaterally symmetrical, worm-like organisms that are surrounded by a strong, flexible noncellular layer called a cuticle
ganglia
is a biological tissue mass, most commonly a mass of nerve cell bodies
, metamerism
is a linear series of body segments fundamentally similar in structure
annuli
A ring- or donut-shaped area or structure
parapodia
are paired, lateral appendages extending from the body segements
dorsal
pertaining to the back or to any dorsum
ventral
of or pertaining to the venter or belly; abdominal
clitellum
is a thickened glandular section of the body wall in earthworms and leeches, that secretes a viscid sac in which the eggs are deposited
, polychaeta
polychaetes are a class of annelid worms, generally marine
oligochaeta
a subclass of animals in the biological phylum Annelida, which is made up of many types of aquatic and terrestrial worms
hirudinea
A class of worms, comprising the leeches that feed on
nerve plexus
is a network of intersecting nerves
nerve cord
is one of the embryonic features unique to chordates
scolex
the attachment organ of a tapeworm, generally considered the anterior, or cephalic, end
radioles
a heavily ciliated feather-like tentacle found in highly organized clusters on the crowns of Canalipalpata