BIO 2.2

• phylum of segmented worms

  Annelida
• spiders, scorpions, mites, ticks, and harvestmen

  Arachnida
• contains eighty percent of all living animals

  Arthropoda
• beetles

  Coleoptera
• egg, larva, pupa, adult

  complete metamorphosis
• crabs, lobsters, shrimp, crayfish

  Crustacea
• class containing leeches

  Hirudinea
• social insects

  Hymenoptera
• egg, nymph, adult

  incomplete metamorphosis
• roundworms

  Nematoda
• class containing earthworms

  Oligochaeta
• crickets and grasshoppers

  Orthoptera
• flatworms

  Platyhelminthes
• class containing marine worms

  Polychaeta
• part of the insect's respiratory system

  spiracles
• mosquitoes, flies, and gnats

  Diptera
• The earthworm's clitellum secretes a protective cocoon into which its eggs are deposited.
• Setae aid the earthworm's movement.
• The earthworm's circulatory system consists of five simple hearts, a ventral vessel, a dorsal vessel, and smaller blood vessels.
• Because earthworms are hermaphroditic, they have both ovaries and testes, and produce both eggs and sperm.
• Tapeworms infect the intestinal tract of humans.
• The tapeworm is able to reproduce in the primary host.
• An arthropod's nervous system consists of a brain, a ventral nerve cord, and specialized sense organs.
• The two divisions of the spider's body are the cephalothorax and the abdomen.
• The chelicerae are not part of the spider's sensory system.
• The spider's prey is digested outside the body.
• Arachnids breathe by means of book lungs.
• Most newly hatched insects do not resemble their parents because of the process of complete metamorphosis.
• During the larval stage of an insect, massive amounts of food are consumed, and thousands of dollars' worth of damage is done to crops.