Flashcards in Chapter 18 Deck (37):
A segmented worm. These organisms include earthworms, polychaetes, and leeches.
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.
Pertaining to the front, or head, of a bilaterally symmetrical animal.
A member of a major arthropod group (chelicerates) that includes spiders, scorpions, ticks, and mites.
A member of the most diverse phylum in the animal kingdom. These members are characterized by a chitinous exoskeleton, molting, jointed appendages, and a body formed of distinct groups of segments.
An arrangement of body parts such that an organism can be divided equally by a single cut passing longitudinally through it. This organism has mirror-image right and left sides.
Member of the clade of animals Bilateria exhibiting bilateral symmetry.
A member of a group of molluscs that includes clams, mussels, scallops, and oysters.
An embryonic stage that marks the end of cleavage during animal development; a hollow ball of cells in many species.
A fluid-containing space between the digestive tract and the body wall.
A carnivorous terrestrial arthropod that has one pair of long legs for each of its numerous body segments, with the front pair modified as poison claws.
A member of a group of molluscs that includes squids and octopuses.
The transformation of a larva into an adult.
A terrestrial arthropod that has two pairs of short legs for each of its numerous body segments and that eats decaying plant matter.
A soft-bodied animal characterized by a muscular foot, mantle, mantle cavity, and radula; includes gastropods (snails and slugs), bivalves (clams, oysters, and scallops), and cephalopods (squids and octopuses).
The process of shedding an old exoskeleton or cuticle and secreting a new, larger one.
A roundworm, characterized by a pseudocoelom, a cylindrical, wormlike body form, and a tough cuticle.
A flexible, cartilage-like, longitudinal rod located between the digestive tract and nerve cord in chordate animals; present only in embryos in many species.
system in which blood is pumped through open-ended
vessels and bathes the tissues and organs directly. In an animal with this system, blood and interstitial fluid are one and the same.
Open Circulatory System
Structures found in the pharynx; found in chordate embryos and some adult chordates.
Pharyngeal Gill Slits
A member of the largest group of annelids.
One of 2 types of cnidarian body forms; a columnar body, hydra like body.
A tail posterior to the anus; found in chordate embryos and most adult chordates.
Post anal tail
Pertaining to the rear, or tail, of a bilaterally symmetrical animal.
An animal with a coelom that develops from solid masses of cells that arise between the digestive tube and the body wall of the embryo. These animals include the molluscs, annelids, and arthropods.
A body cavity that is in direct contact with the wall of the digestive tract.
An arrangement of the body parts of an organism like pieces of a pie around an imaginary central axis. Any slice passing longitudinally along the organism's central axis divides it into mirror-image halves.
A toothed, rasping organ used to scrape up or shred food; found in many molluscs.
Subdivision along the length of an animal body into a series of repeated parts called segments.
An organism that is anchored to its substrate.
An aquatic animal characterized by a highly porous body.
An aquatic animal that sifts small food particles from the water.
A parasitic flatworm characterized by the absence of a digestive tract.
One of a group of invertebrate chordates.
Pertaining to the underside, or bottom, of a bilaterally symmetrical animal.
One of the three main parts of a mollusc, containing most of the internal organs.