Transcript arthropod powerpoint

PHYLUM: ARTHROPODA
• arthro – Greek for JOINTED
• poda – Greek for FOOT
• JOINTED FEET!!!
THE KEY FEATURE OF ARTHROPODS
• An exoskeleton
EXOSKELETON
• Does not grow so the arthropods must molt
• http://www.youtube.com/watch?v=n6iQ96emYE0
• http://www.youtube.com/watch?v=ngebZ6n1vVY
MOLTING
NOTICE THE HOLE?
OTHER FEATURES:
• Malpighian tubules – excretion
• Many have complex nervous systems
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Better eyes
Sensory abilities
Social abilities
Antennae
• Open circulatory system
• Hemocoel is the major body cavity
MORE FEATURES
• Tracheal system – respiratory system connected to
the atmosphere
• Fertilization is mostly internal
• Some eggs hatch into adult looking form
• Some have a larval stage which doesn’t resemble
the adult
• Metamorphosis!!
FOUR SUBPHYLA
• Trilobitmorpha
• Trilobites
• Chelicerata
• Arachnida (spiders, scorpions, ticks, mites)
• Crustacea
• Lobsters, crabs, and crayfish
• Uniramia
• Myriapods and insects
TRILOBITES ARE EXTINCT
CHELICERATES HAVE NO
ANTENNAE
CHELICERATES HAVE NO
ANTENNAE
CHELICERATES HAVE NO
ANTENNAE
CRUSTACEA
• 2 pairs of antennae
3 pairs of appendages around the mouth
• Modified body appendages for walking and
swimming
• Branched appendage
CRUSTACEA
CRUSTACEA
UNIRAMIA
• Uniramous
• Jointed but UNBRANCHED appendages
UNIRAMIA - MYRIAPODS
• Millipedes and centipedes
UNIRAMIA: INSECTS!!!!
• All have 3 pairs of legs (6 feet) on the thorax
• All have a single pair of antennae
• All have a pair of compound eyes
ECOLOGICAL ROLES
+ pollinate many of the world’s plants
(integral part of agriculture)
“If the bee disappeared off the surface of the
globe man would only survive for four years” –
Albert Einstein
+ arthropod predators kill pest organisms by
the millions
+ direct/indirect food source for countless
organisms
+ lobsters, crab, crayfish and shrimp are an
important food source for humans