Vocabulary

Arachnid- chelicerata arthropod with four pairs of legs on its cephalothorax and no antennae

Arthropod- animal having a segmented body, an exoskeleton containing chitin, and a series of jointed appendages belonging to the phylum arthropoda

Appendages- extended body parts such as arms or legs

Chelicerate- arthropod characterized by a two-part body and mouthparts called chelicerate

Cephalothorax- fused head and upper body of some arthropods
Spiracles- a small paired aperture along the side of the thorax or abdomen of an insect or spider through which air enters and leaves

Chitin- complex carbohydrate found in arthropod exoskeletons and fungal cell walls

Crustacean- arthropod characterized by a stony exoskeleton, two pairs of antennae and mandibles

Exoskeleton- system of supporting structures covering the outside of the body

Ganglia- small cluster of nerve cells

Gills- the organ that fish and some other aquatic animals use to breathe, consisting of a membrane containing many blood vessels through which oxygen passes.

Mandible- mouthpart designed for biting and grinding food

Metamorphosis- series of dramatic changes in body form in the life cycle of some animals

Molt- to shed an exterior layer of skin, feathers, or an exoskeleton

Pheromone- specific chemical messenger produced by an organism that effects the behaviour and development of other individuals in the species

Pupa-resting stage of metamorphosis in which tissues are of an insect are organized into the adult form

Sinuses- a widened channel containing blood, especially venous blood

Tracheae-a tube in insects and related air-breathing animals through which air is drawn into the body by the pumping action of the abdominal muscles

Tracheal system- the system to do with the tracheae

Trilobite- sea-dwelling organism belonging to the oldest, now extinct, subphylum of arthropods

Uniramian- member of the largest subphylum of arthropods contains centipedes millipedes and insects