water is drawn in through pores into a cavity called the spongocoel, and out through opening called osculum
Body plan of a cnidarian
sac w/ central digestive compartment = gastrovascular cavity, which serves as a hydrostatic skeleton
(mostly free-living flatworms), generally non-parasitic
by parthenogenesis; females produce offspring by unfertilized eggs
Members of class polychaetes have..
paddle-like parapodia that work as gills and aid in locomotion
Many legs. Each trunk segment has two pairs of legs.
Echinoderms have a unique..
water vascular system, a network of hydraulic canals branching into tube feet that function in locomotion, feeding, and gas exchange.
A radially symmetrical animal that has two embryonic tissue layers probably belongs to which phylum?
Which cells in a sponge are primarily responsible for trapping and removing food particles from circulating water?
Corals are most closely related to which group?
What would be the most effective method of reducing the incidence of blood flukes in a human population?
Reduce the freshwater snail population
A lophophore is used by ectoprocts and brachiopods for...
A terrestrial mollusc without a shell belongs to which class?
Which molluscan class includes marine organisms whose shell consists of eight plates?
Many of these annelids are parasites
Of the annelid classes below, which make castings that are agriculturally important
Some species of this annelid class release an anticoagulant that is of medical significance?
A characteristic of nematodes
Only have longitudinal muscles
Humans most frequently acquire trichinosis by
eating undercooked pork
Infection with which parasite might cause excessive elasticity in human skeletal muscles
Which of the following are entirely, or partly, composed of calcium carbonate?
coral animals' exoskeletons
Among the invertebrate phyla, phylum Arthropoda is unique in possessing members that have
Which of the following characteristics most likely explains why insects are so successful at dispersing to distant environments?
The possession of two pairs of antennae is a characteristic of
Protostomes that have an open circulatory system and an exoskeleton of chitin are part of which phylum?
Protostomes with a unique drape of tissue that may secrete a shell are part of which phylum?
Deuterostomes that have an endoskeleton are part of which phylum?
Protostomes that have a closed circulatory system and obvious segmentation are part of which phylum