NEM 10V Lecture Notes - Lecture 33: Chitin, Myriapoda, Lyme Disease
Nematology
Part 7 Anthropods:
• Arthropods are bilaterally symmetric invertebrates with jointed appendages, and an
exoskeleton made of chitin.
• There are four groups of Arthropods.
• The Myriapoda are the centipedes and millipedes that have an elongated body with many
similar segments, and either one or two pairs of legs per segment.
• The head has paired antennae.
• The Chelicerata, also called Arachnids, are the spiders, scorpions, mites and ticks that
have four pairs of walking legs and no antennae.
• Crustaceans are mostly marine arthropods that have two pairs of antennae, and include
crabs, barnacles, shrimp and lobster.
• The Hexopoda or Insects, have a segmented body with three parts (head, thorax,
abdomen), have three pairs of legs, and one pair of antennae.
• The capacity for flight distinguishes insects from other invertebrates and is the reason for
their success because if allows escape from predators and allows them to travel widely
and exploit a wide variety of habitats.
• Flight requires rapid and efficient gas exchange that is provided by a network of narrow
branching tubes called trachea that conduct air throughout an insect’s body.
• Air flow in and out is controlled by openings called spiracles.
• Social behavior and specialization of roles is an adaptation of termites, ants and bees that
live in well organized communities.
• Honeybees are important pollinators of many agricultural crops. As such, they are likely
to come into contact with various pesticides used to control pest insects.
find more resources at oneclass.com
find more resources at oneclass.com
