-over a million species and 10000000000000000000 individuals
-mostly have three different segments; head, thorax, abdomen
-have joined appendages
-exoskeleton made of citin and will molt to grow
Most insects have highly branched trachial tubes that goes to every cell. They have spiracles and no lungs. Aquatic
anthropods have gills: outfoldings of the ectoderm. Spiders have lungs which are infoldings of the ectoderm.
-more complex and well developed
-vision is simple compound eye
-well developed nervous system with ganglia
-open circulatory system
-mouth, stomach, intestine, rectum
-mostly seperate sexes: water anthropods have external
fertilization, land anthropods have internal fertilization
Class Arachnida includes spiders, scorpians, and ticks and all lack mandables. They have six pairs of walking legs
except ticks and mite which have one and all have four pairs of walking legs.
Class Crustacea includes lobster,
shrimp, crabs, barnacles, and daphnia. They have 2 pairs of atennae and usually five pairs of walking legs.
Chilopoda are the centipedes and have one leg per segment. They are fast, carnivorous and venomous.
are the millipedes with two legs per segment. They are slow, but some species can get very large. When threatened they produce
a unpleasant smelling gas.
Class Insecta includes flies, miquitoes, dragon and butterflies, wasps and hornets,
bettles, and moths. They go through metamorphosis and have internal fertilization.