invertebre Flashcards
primitive invertebrate animals comprising the sponges and having a cellular grade of construction without true tissue or organ formation but with the body permeated by canals and chambers through which a current of water flows and passes in its course through one or more cavities lined with choanocytes.
Porifera
a phylum of more or less radially symmetrical invertebrate animals that lack a true body cavity, possess tentacles studded with nematocysts, and include the hydroids, jellyfishes, sea anemones, and corals.
Cnidaria
The annelids, also known as the ringed worms or segmented worms, are a large phylum, with over 22,000 extant species including ragworms, earthworms, and leeches.
Annelida
a coelenterate of an order that includes the hydras. They are distinguished by the dominance of the polyp phase.
Hydroid
a free-swimming marine coelenterate with a jellylike bell- or saucer-shaped body that is typically transparent and has stinging tentacles around the edge.
Jellyfish
The flatworms, flat worms, Platyhelminthes, Plathelminthes, or platyhelminths
Platyhelminthes
a phylum related to the Aschelminthes and comprising elongated cylindrical worms without an epithelial coelomic lining, with dorsal and ventral nerve cords, and with lateral excretory ducts that are parasites of humans, animals, or plants or free-living dwellers in soil or water and are known as roundworms, eelworms, …
Nematoda
a small nematode worm that is an internal parasite of vertebrates.
Pinworms
a parasitic flatworm, the adult of which lives in the intestine of humans and other vertebrates. It has a long ribbonlike body with many segments that can become independent, and a small head bearing hooks and suckers.
Tapeworms
an aquatic mollusk that has a compressed body enclosed within a hinged shell, such as oysters, clams, mussels, and scallops.
Bivalves
a mollusk of the large class Gastropoda, such as a snail, slug, or whelk.
Gastropods
Coelomate animals or Coelomata (also known as eucoelomates — “true coelom”) have a body cavity called a coelom with a complete lining called peritoneum derived from mesoderm (one of the three primary tissue layers). … Most bilateral animals, including all the vertebrates, are coelomates.
Coelomate
Definition of acoelomate. : an invertebrate lacking a coelom especially : one belonging to the group comprising the flatworms and nemerteans and characterized by bilateral symmetry and a digestive cavity that is the only internal cavity.
Acoelomate
symmetry around a central axis, as in a starfish or a tulip flower.
Radial Symmetry
lack of equality or equivalence between parts or aspects of something; lack of symmetry.
Asymmetry
