| A | B |
|---|
| vertebrate | the classification of animals possessing a backbone |
| invertebrate | the classification of animals not possessing a backbone |
| vertebra | the individual bones that make up the backbone |
| endoskeleton | a skeleton made of bones found inside the body providing support for the body |
| exoskeleton | a rigid external covering in arthropods that provides support and protection |
| chitin | a polysaccharide that forms a rigid structure that provides protection for arthropods |
| shell | a rigid container made out of calcium carbonate that some invertebrates use for protection and for housing |
| ectothermic | an organism that cannot control its internal temperature |
| hermaphroditic | a situation in which a single individual can produce both male and female gametes |
| metamorphosis | a developmental stage where an immature organism goes through extensive changes in body plan to enter an adult stage |
| regeneration | a term used to describe the ability of some organisms to regrow a missing body part or even give rise to a new organism |
| Phylum Porifera | the phylum of invertebrates that contains sponges |
| spongin | a flexible support structure made of protein found in sponges |
| choanocytes | cells found in sponges that have a flagella and a collar |
| amoebocytes | cells found in sponges that deliver nutrients to other cells in the sponge |
| osculum | the central opening of a sponge from which recently filtered water exits |
| spicules | rigid structures that come in many shapes that are used to support certain sponges |
| Phylum Ctenophora | the phylum that contains comb jellies |
| Phylum Cnidaria | they phylum that contains jellyfish, sea anemones, coral, and hydra |
| ectoderm | the outer layer or epidermis of ctenophores and cnidarians |
| endoderm | the gastrodermis or inner layer of ctenophores and cnidarians |
| mesoglea | a gelatinous substance between the ectoderm and endoderm of ctenophores and cnidarians |
| colloblasts | cells located on the tentacles of comb jellies that release a sticky substance when struck by prey |
| polyp | the asexually reproducing stage of a cnidarian life cycle that is stationary and often cylindrical in shape |
| medusa | the sexually producing stage of a cnidarian life cycle that is free swimming and shaped like an umbrella |
| planula | the free-swimming, flat larva form of cnidarians |
| nematocysts | stinging cells located on the tentacles of cnidarians |
| sea anemones | cnidarians that look like plants and spend their lives in the polyp stage |
| coral | cnidarians that look like plants and spend their lives in the polyp stage but surround themselves with a hard structure made of calcium carbonate |
| hydra | cnidarians that spend most of their lives in the polyp stage and attach to solid surfaces with a basal disk. They can reproduce by budding. |
| Phylum Platyhelminthes | the phylum that contains the flatworms |
| bilateral symmetry | the type of body plan capable of being divided into two halves that are mirror images of each other |
| radial symmetry | the type of body plan where an organism can be divided into equal parts from a center point |
| incomplete digestive system | a digestive system in which there is only one body opening |
| complete digestive system | a digestive system in which there is a mouth and an anus |
| pharynx | a muscular structure that connect the mouth to the esophagus |
| eyespots | light-sensitive structures that help guide an organism towards areas where food is more likely to be found |
| primary host | the host in which a parasite develops into its adult form |
| intermediary host | the host that a parasite uses to reach its definite host |
| proglottids | a series of identical segments that make up the bodies of tapeworms |
| Phylum Echinodermata | the phylum that makes up sea stars, brittle stars, sea urchins, sand dollars, feather stars, and sea cucumbers |
| water system | the system used by members of Echinodermata to operate tube feet |
| tube feet | the suction cup like feet that members of echinodermata use to move and grasp objects |
| Phylum Mollusca | the phylum that contains snails, slugs, octopus, squid, clams, oysters, mussels, and scallops |
| visceral mass | the name for the body of a mollusk |
| foot | the base of a mollusk used for locomotion and anchoring |
| mantle | a layer of tissue that covers a mollusk's organs |
| radula | a file-like rasping tool that enable mollusks to feed on algae |
| class Gastropoda | the class of mollusks that include snails and slugs |
| class Cephalopoda | the class of mollusks that contain octopus, squid, cuttlefish, and nautilis |
| class Bivalvia | the class of mollusks that produce a two-part shell and include clams, oysters, mussles, and scallops |
| Phylum Nemotoda | the phylum that contain roundworms |
| T. canis | the roundworm that puppies commonly are infected with |
| Trichinella spiralis | the roundworm that uses pigs and bears as host and causes trichinosis in humans |
| Phylum Annelida | the phylum that contains segmented worms like earthworms |
| closed circulatory system | the type of circulatory system in which blood is confided to blood vessels |
| open circulatory system | the type of circulatory system in which blood is pumped into cavities called hemocoels |
| setae | bristles on the lower surface of members of Annelida that help in mobility |
| dorsal | the anatomical term referring to the upper or back portion of an organism |
| ventral | the anatomical term referring to the underside or belly of an organism |
| anterior | the anatomical term referring to the head of an organism |
| posterior | the anatomical term referring to the end of an organism that is opposite the head |
| clitellum | the thickened section of an earthworm located anteriorly used in reproduction |
| prostomium | the front part of the head of an earthworm that is in front of the mouth |
| crop | the structure that is part of the digestive system of an earthworm where dirt is stored until it can travel to the gizzard |
| gizzard | the structure that is part of the digestive system of an earthworm that grinds and crushes dirt |
| intestine | the part of the digestive system where nutrients are absorbed into the blood |
| Phylum Arthropoda | the phylum that contains insects, crustaceans, arachnids, and myriapods |
| cephalothorax | the name given to the fusion of the head and thorax |
| molting | the shedding and replacing of an old outer covering |
| compound eye | an eye that is made up of many small viewing units, each which produces an image |
| simple eye | an eye that is made up of one lens which produces one image |
| class Arachnid | the class of arthropods that contain spiders, mites, ticks, scorpions, daddy-long-legs |
| carapace | a hard covering over the cephalothorax of arthropods |
| chelicerae | a pair of appendages found in arachnids that function like jaws |
| pedipalps | a pair of appendages found in arachnids that serve as claws or sensory organs |
| venom | a poisonous substance that certain organisms inject into their prey |
| spinneret | a silk-spinning organ of a spider |
| proboscis | a tubular sucking organ |
| telson | the final segment of the body of an arthropod |
| green glands | special structures in crustaceans that remove waste from the blood so that it can be excreted |
| crustaceans | the subphylum of Arthropoda that contains crabs, lobsters, crayfish, and shrimp |
| decapod | the name given to members of Arthropoda that have five pairs of legs on their thorax like crabs |
| entomology | the study of insects |
| chrysalis | the hard, smooth covering of a butterfly pupa during its sheltered state when it is transforming into an adult butterfly |
| cocoon | the silk covering of a moth pupa during its sheltered state when it is transforming into an adult moth |
| pollinator | an animal that carries pollen from one plant to another to aid in fertilization |
| millipede | a myriapod that has two sets of legs on each body segment |
| centipede | a myriapod that has one set of legs on each body segment |
| chordate | an invertebrate that has a notochord |
| Phylum Chordata | the phylum of invertebrates that includes sea squirts and lancelets |
| notochord | a rod-like structure that is made of cartilage that provides support and protection to a nerve chord |
| Cambium Explosion | the theoretical time period in which there is a sudden appearance of all the basic invertebrate body plans in a very short period of time |
