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62 Cards in this Set

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  • Back
segmented worms
alimentary canal
A digestive tract consisting of a tube running between a mouth and an anus.
An amoeba-like cell that moves by pseudopodia, found in most animals; depending on the species, may digest and distribute food, dispose of wastes, form skeletal fibers, fight infections, and change into other cell types.
(clams and their relatives) have a hinged shell divided into two halves.
book lung
An organ of gas exchange in spiders, consisting of stacked plates contained in an internal chamber.
includes squids and octopuses, carnivores with beak–like jaws surrounded by tentacles of their modified foot.
include spiders, ticks, and mites. They have an anterior cephalothorax and a posterior abdomen. The most anterior appendages are modified as chelicerae (either pincers or fangs).
Class Anthozoa
contains the sea anemones and corals, which occur only as polyps.
Class Cestoda
tapeworms, all of which are parasites and lack a digestive tract.
Class Hydrozoa
usually alternates polyp and medusa forms, although the polyp is more conspicuous.
Class Polyplacophora
composed of the chitons, oval–shaped marine animals encased in an armor of eight dorsal plates.
Class Scyphozoa
jellies (medusae) are the prevalent form of the life cycle.
Class Turbellaria
made up of mostly free–living, primarily marine species.
mainly marine carnivores possessing tentacles armed with cnidocytes that aid in defense and the capture of prey. Two body forms are sessile polyps and floating medusae.
One of a pair of clawlike feeding appendages characteristic of cheliceriforms.
An arthropod that has chelicerae, and a body divided into a cephalothorax and an abdomen. Living cheliceriforms include sea spiders, horseshoe crabs, scorpions, ticks, and spiders.
A flagellated feeding cell found in sponges. Also called a collar cell, it has a collar-like ring that traps food particles around the base of its flagellum.
class Gastropoda
the snails and their relatives, possess a single, spiraled shell. Embryonic torsion of the body is a distinctive characteristic. Many slugs lack a shell or have a reduced shell.
class Hirudinea
bloodsucking parasites...leeches
class Polychaeta
possess paddle–like parapodia that function as gills and aid in locomotion.
A specialized cell for which the phylum Cnidaria is named; contains a capsule containing a fine coiled thread, which, when discharged, functions in defense and prey capture.
A member of the group of crustaceans that includes lobsters, crayfish, crabs, and shrimps.
(sea stars and their relatives) have a water vascular system ending in tube feet used for locomotion and feeding. The radial anatomy of many species evolved secondarily from the bilateral symmetry of ancestors. A thin, bumpy, or spiny skin covers a calcareous endo–skeleton.
A hard encasement on the surface of an animal, such as the shell of a mollusc or the cuticle of an arthropod, that provides protection and points of attachment for muscles.
dorsoventrally flattened animals with a gastrovascular cavity.
General Characteristics of Arthropods
Variation in arthropod morphology consists mainly in specializations of groups of segments and in appendages. The arthropod exoskeleton, made of protein and chitin, undergoes regular ecdysis (molting).
gastrovascular cavity
An extensive pouch that serves as the site of extracellular digestion and a passageway to disperse materials throughout most of an animal’s body.
An individual that functions as both male and female in sexual reproduction by producing both sperm and eggs.
exceed all other animals combined in species diversity. Flight has been an important factor in the success of this group
coelomates that have a lophophore, a horseshoe–shaped, suspension–feeding organ bearing ciliated tentacles.
have a muscular foot, a visceral mass, and a mantle
Millipedes are wormlike, with a large number of walking legs. They were among the first animals to live on land. Centipedes are terrestrial carnivores with poison claws.
mantle cavity
A water-filled chamber that houses the gills, anus, and excretory pores of a mollusc.
The floating, flattened, mouth-down version of the cnidarian body plan. The alternate form is the polyp.
A gelatinous region between the two layers of cells of a sponge.
nonsegmented pseudocoelomates covered by a tough cuticle. whip-like motion due to longitudinal muscles only
have a unique retractable tube (proboscis) used for defense and prey capture. A fluid–filled sac is used to extend the proboscis.
A stinging, capsule-like organelle in a cnidocyte.
includes earthworms and various aquatic species.
open circulatory system
A circulatory system in which fluid called hemolymph bathes the tissues and organs directly and there is no distinction between the circulating fluid and the interstitial fluid.
A large opening in a sponge that connects the spongocoel to the environment.
A type of reproduction in which females produce offspring from unfertilized eggs.
A free-living flatworm found in unpolluted ponds and streams.
The sessile variant of the cnidarian body plan. The alternate form is the medusa.
Found mainly in fresh water, many rotifer species are parthenogenetic.
A straplike rasping organ used by many molluscs during feeding.
lack true tissues and organs. They suspension feed by drawing water through pores; choanocytes (flagellated collar cells) ingest suspended food.
The central cavity of a sponge.
suspension feeder
An aquatic animal, such as a clam or a baleen whale, that sifts small food particles from the water.
live as parasites in or on animals...Flukes
An extinct arthropod with pronounced segmentation and appendages that varied little from segment to segment.
trochophore larva
Distinctive larval stage observed in certain invertebrates, including some annelids and molluscs.
tube foot
One of numerous extensions of an echinoderm’s water vascular system. Tube feet function in locomotion, feeding, and gas exchange.
visceral mass
One of the three main parts of a mollusc, containing most of the internal organs.
water vascular system
A network of hydraulic canals unique to echinoderms that branches into extensions called tube feet, which function in locomotion, feeding, and gas exchange.
A fold of tissue in molluscs that drapes over the visceral mass and may secrete a shell.
A characteristic of gastropods in which the visceral mass rotates during development.
A segmented coelomate with a chitinous exoskeleton, jointed appendages, and a body formed of distinct groups of segments.
A process in arthropods in which the exoskeleton is shed at intervals, allowing growth by the production of a larger exoskeleton.
A member of a subphylum of arthropods that includes lobsters, crayfish, crabs, shrimps, and barnacles
A member of one of the largest groups of crustaceans, which includes terrestrial, freshwater, and marine species. Among the terrestrial isopods are the pill bugs, or wood lice.
Any of a group of small crustaceans that are important members of marine and freshwater plankton communities.