Transcript Phylum Arthropoda

Phylum Arthropoda
Chapter 38
By: Chris Brennan
Honors Biology Pd. 6 (2003)
Modified by Mrs. M (2006)
Editor Dylan Wartluft (2006)
Arthropods
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Key Characteristics
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Invertebrates
Bilateral symmetry
Coelom
Segmentation
Exoskeleton made of chitin
Jointed Appendages
Distinct Head, usually with
compound eyes
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http://www.bio.indiana.edu/facultyresearch/sciencepics/kumar5.jpg
Definitions
Compound Eyes - eye made of thousands of individual
units.
Exoskeleton – hard external covering of some
invertebrates
Molting – a periodic shedding of an arthropod’s
exoskeleton
Spiracles – respiratory opening on certain arthropods that
allows for passage of air into the body
Tracheae – in certain arthropods, fine tubes that extend
into the interior of the body, used for gas exchange
Thorax – mid-body region in arthropods
http://manduca.entomology.wisc.edu/images/manducatrachea.jpg
Definitions
Cephalothorax – the body region in some arthropods that
consists of a head fused with a thorax
Pedipalps - in Arachnids, a second pair of appendages that
are modified to catch and handle prey
Carapace –shield like plate covering the cephalothorax of
decapods
Swimmerets – found in Crustaceans, attached to the
underside of the abdomen and used for swimming and
reproduction
Chelipeds – in Crustaceans, a modified pair of legs that is
used to catch and handle prey for feeding
Mandible – chewing mouthpart found in many arthropods
Chelicerae – paired mouthparts of arachnids and their
relatives that are modified into fangs or pinchers
Examples
Class Insecta: ant, butterfly, ladybug
 Class Crustacea: lobster, shrimp
 Class Arachinida: spider, tick, mite
 Class Chilopoda: centipedes
 Class Diplopoda: millipedes
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Click images for links
Nutrition
Herbivores
 Carnivores
 Parasites
 Scavengers
 GREAT VARIETY
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Systems
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Digestive: 2 openings with specialized
organs.
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Excretory: Varies. Terrestrial
arthropods have malpighian tubules.
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Nervous: Brain and sensory organs.
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Reproductive: Sexual with separate
sexes.
Systems
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Support: Exoskeleton (advantages and
disadvantages)
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Respiration: Spiracles and trachea,
gills, book lungs
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Circulation: Open circulatory system
Class Crustacea
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Description
– 2 body sections:
cephalothorax, abdomen
– 2 pairs of
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Antennae
Mandibles
– Mostly aquatic (GILLS)
Interesting Facts:
•Lobster blood is clear 
•Lobsters can regenerate
legs, claws, and antennae
•Female lobsters carry
thousands of eggs on their
swimmerets
Examples
– Crayfish, lobsters, and
crabs.
Class Archnida
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Description
– 2 body sections:
cephalothorax and
abdomen
– Terrestrial
– Use book lungs and
tracheae to breathe
– 4 pairs of legs
Examples: spider, tick,
Scorpion, mite
Interesting Facts:
•Scientists have combined the DNA
from a goat and spider to create an
animal which produces silk five
times stronger than steel
•There may be 1000 spider eggs in
an egg sac the size of a pea
• A jumping spider can jump forty
times its own body length
Anatomy
Class Chilopoda
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Description
– Flat body
– Contains 15 - 170+
segments on body
– 1 pair of legs on Interesting Facts:
•Centipedes can live up to 6 years
each segment
•Centipedes can grow up to a half foot
•Centipedes run a way from predators or
– Carnivore
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Example
– Centipede
fight back
Class Diplopoda
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– Rounded Body
– Body contains 15 –
200 segments
– 2 pairs of legs
attached to each
segment
– Herbivores
Interesting Facts:
•Most millipedes are
harmless but a few are
dangerous
•One millipede is almost
luminescent, but it is blind
•Some millipedes live in a
colony of ants cleaning up
the ants debris. This
millipede will even move
when the ants move.
Description
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Example
– Millipede
Class
Name means
a.k.a.
#pr. Legs/seg
Body shape
Eating habits
Aggressiveness
Breathing
Chilopoda
Diplopoda
Class Insecta
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Description
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3 body sections: Head, thorax, and abdomen
3 pairs of legs, attached to thorax
Wings (usually)
Spiracles and Trachea
Interesting Facts:
•40,000 ants have
collectively the same size
brain as a human
•Ants live about 45-60 days
•There are over 10000
known species of ants
Order
Coleoptera
Diptera
Lepidoptera
Hymenoptera
Odonata
Orthoptera
Siphonaptera
Examples
Mimicry
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Mullerian Mimicry – REAL
– Species that have a particular defense
mechanism have similar coloration
– Ex. Red/Black = Poison; Yellow/Black
stripes = sting (bees, wasps)
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Batesian Mimicry – FAKE
– Disguised to look like it has a defense
mechanism, but it’s harmless.
– Ex. Hover fly = stripes; Viceroy butterfly =
monarch look-alike
Metamorphosis
Complete
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Contains 4 parts
– Egg
– Larva (often called
caterpillar)
– Pupa in crysalis or
cocoon
– Adult
Example: Butterfly
Incomplete
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Includes 3 parts
– Eggs
– Nymph
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Smaller
non-functioning wings
cannot reproduce
– Adult
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Example: Grasshopper
molt
scarab.msu.montana.edu
Ecological Impact
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Positive
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Pollinators
Decomposers
Food source
Indicate stream
health
– Forensic value
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Negative
– Destroy crops
– Carry disease
Citations for Slide 5
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www.cogsci.indiana.edu/farg/harry/bio/zoo/ant.jpg
fohn.net/monarch-butterfly-pictures/monarchbutterfly_large.jpg
www.vifishandwildlife.com/Education/FactSheet/Im
ages/Lobster.jpg
www.rammerjammeryellowhammer.com/weblog/shr
imp-1.jpg
www.timart.be/Npaginas/foto/wolf_spider.jpg
http://ppdl.org/dd/images/centipede.jpeg
http://www.uidaho.edu/soid/entomology/Home_&_Garden/millipede.jpg