Arthropods - Invertebrates that have jointed limbs
and segmented bodies covered by an exoskeleton, or outside shell.
Includes crustaceans, insects, centipedes, millipedes, and spiders.
plants - Refers to mosses, liverworts, ferns and
- Neither animals, plants, fungi, or prokaryotes. Comprised of
eukaryotic microorganisms and their immediate descendants, all
nucleated algae (including the seaweeds), undulipodiated (flagellated)
water molds, the slime molds and slime nets, and the protozoa.
- Lacking chlorophyll fungi feed on decaying matter or living
organisms. Most fungi reproduce by forming spores, and they usually
have cell walls that contain chitin or cellulose. Includes mildews,
molds, mushrooms, plant rusts, and slime molds.
- Live in aquatic or moist environments. Most mollusks have a
hard shell enclosing a soft body. All mollusks have a mantle
(a fleshy extension of the body wall) that hangs down on each
side of the visceral mass (main bulk of the body). Includes oysters,
mussels, clams, snails, slugs, limpets, squids, cuttlefish, and
- Defined by the presence of three features: 1) single dorsal
nerve chord, 2) a cartilaginous rod, the notochord, which forms
dorsal to the primitive gut in the early embryo, and 3) the presence,
at some stage in the life cycle, of gill slits in the pharynx
or throat. Includes all mammals, birds, amphibians, reptiles,
and vertebrate fish.
- Round, tapered, thin worms; not segmented.
- Refers to Archea and Eubacteria, simple, unicellular organisms.
- Parasitic, self-replicating, nucleic acid entities.