Arthropods!

Arthropods: Arthropods constitute over 90% of the animal kingdom.

The word Arthropod literally means jointed legs. ***First phylum to have joints***

They are invertebrates (no backbone)

They have true appendages.

Muscular-SkeletalThe body is segmented, the segments usually

grouped in two or three distinct regionsExoskeleton made of chitin

When they outgrow their exoskeleton, they molt!

MoltingPaired segmented appendages.

DigestionTube from mouth to anusDivided into segments:

the foregut, the midgut, and the hindgut

NervousAnterior ganglion or brain and paired nerve

cordsSome have developed sensory ability

CirculationHave an open circulatory system that carries

food, but not oxygen throughout its bodyBlood is often green since it does not carry

oxygenThe heart is a simple tube running along the

back

RespirationRespiration by means of gills or book lungs

and spiracles

ReproductionThe sexes are nearly always separateException: barnacles (hermaphrodites) and

some insects (parthenogenesis)

ExcretionPasses waste

out of its anus from the hindgut

No nephridia *** Instead they

have malpighian tubules***

SymmetryBilateral Symmetry