ARTHROPODS

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ARTHROPODS

• 86 of all described species on Earth.
• About a billion billion insects are alive at any
  time 160 million insects for each person on
  Earth!
• Ants alive today would form a chain that would
  circle the Earth 125,000 times.

Click to see The Arthropod Story from Berkely
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Arthropod Characteristics

• Jointed Legs

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Arthropod Characteristics
Exoskeleton
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Arthropod Characteristics
Exoskeleton

• Outer covering that provides support and
  protection
• But, doesnt grow so must be shed
• After shed, the new materials are secreted onto
  the surface of the arthropod where they harden
  into new exoskeleton
• Materials include waxes, etc.

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Kingdom AnimaliaPhylum Arthropoda

• Class Insecta insects
• 3 body parts, 6 legs, 2 antennae
• Flies, ants, beetles, etc.

• Class Arachnida arachnids
• 1-2 body parts, 8 legs, no antennae
• spiders, scorpions, ticks, mites

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COMPLETE METAMORPHOSIS

• Egg gtgt Larva gtgt Pupa gtgt Adult
• butterflies, flies, beetles, etc.
• Advantages
• Larvae concentrate on eating
• Adults concentrate on reproducing.
• Disadvantage
• Pupae are vulnerable to predation

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INCOMPLETE (SIMPLE) METAMORPHOSIS

• Egg gtgt Nymph (small adult) gtgt Adult
• Grasshoppers, True Bugs, Cicadas, Dragonflies,
  etc.

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RESPIRATORY SYSTEM

• Brings air directly to tissues via holes through
  the exoskeleton called spiracles that then lead
  to the rest of the body via tracheae.

link
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RESPIRATORY SYSTEM
Spiracles