Download Centipedes

Arthropods
• Arthropoda - “jointed legs.
• Largest animal phylum;
includes insects, spiders
shrimp, and centipedes.
• Jointed appendages include,
legs, antennae, claws, &
pinchers.
• Body Cavity & digestive system; possess
mouth & anus.
• Open circulatory system w/ a heart
• Nervous system is similar to annelids, but
with larger brains
• Have compound eyes to detect color &
motion
• Have featherlike gills, book gills or book
lungs to respire
Skeletal Structure
• Have an external structure called an
exoskeleton.
• Made up a protein & a carbohydrate called
chitin.
• Sheds its exoskeleton as it grows in a process
called molting.
• Is vulnerable to predators while new
exoskeleton hardens
Class Insecta
Insects are largest
invertebrate class.
• Three body regions: head, thorax, &
abdomen.
• Head contains a pair of antennae, eyes,
& a mouth.
• Thorax has 3 pair of jointed
legs, & 1 or 2 pair of wings in
most species.
• Abdomen is divided into 11
segments (No wings or legs
attached to abdomen).
• Only invertebrates capable of
flight.
- allows them to find food, home, and
mates better and it allows them to
escape predators.
• Possess both simple & compound eyes
(detect color and movement).
• Antennae are used for touch & smell.
• Open circulatory system carries food and
waste.
• O2 enters and CO2 exits through spiracles
(holes) on the abdomen and thorax.
Reproduction
• Reproduce sexually.
• Many undergo metamorphosis series of changes controlled
by hormones.
• Two types: Complete &
Incomplete.
Complete Metamorphosis
• Most insects such as:
butterflies, beetles, ants, bees,
moths & flies develop through
complete Metamorphosis.
• 4 stages: Egg, Larva, Pupa
(resting), & Adult.
Incomplete
Metamorphosis
• Grasshoppers, crickets & lice.
• Three stages: egg, nymph,
adult
• Nymph is a wingless version
of the adult.
• The exoskeleton, jointed
appendages, and wings allow them
to live on land and fly.
• Small size allows them to hide
from enemies and live in a wide
range of environments.
Crustaceans
• Crabs, crayfish, lobsters, shrimp,
barnacles, water fleas, & pill
bugs.
- Cephalothorax (fusion of head &
thorax) & abdomen
- 5 pairs of walking legs, 1st pair are
claws.
Carapace
Tail
Abdomen
Cephalothorax
Swimmerets
Mandible
First antenna
Second antenna
Walking legs
Cheliped
• 4 others are walking legs. 5 pairs
of swimmerets on abdomen help in
locomotion & reproduction.
• Lost appendages can be
regenerated.
• Telson is a muscular tail possessed
by crayfish, shrimp & lobster.
• Possess compound eyes.
• One or two antennae
• Jaws called mandibles are used for
crushing food.
• they force water over the gills
for breathing.
• Important food source for humans.
Arachnids
• Class containing spiders,
scorpions, mites, & ticks.
• Possess cephalothorax &
abdomen.
• 4 pairs of legs, but lack
antennae.
• Poison glands, stingers, or fangs are used to
subdue prey.
• Some have a pair of modified appendages
(pedipalps) used in feeding & prey capture.
Pedipalp
•Respiration occurs
through spiracles & book
lungs.
Spiders
• Poisonous bite
paralyzes prey.
• Digestive enzymes
then liquefy organs,
which are drunk
later.
2 Poisonous Spiders:
1.Black widow
2.Brown recluse
Black Widow
• Latrodectus mactrans - Black
Widow.
• Red hour glass design on
abdomen.
- Only females bite are
dangerous, extremely poisonous.
Related species:Australian Brown
Widow & Japanese Red Widow
Brown Recluse
• Loxceles reclusa - Brown
Recluse.
• Southern Spider/ house spider.
• Bite causes massive cell
destruction.
• Related species are dev. potent
venom.
Scorpions
• Pedipalps are enlarged into
claws to hold prey to be stung
by poisonous tail stinger.
• Chew their prey
Ticks, Chiggers, &
Mites
• Parasites that can cause diseases
such as Lyme’s Disease (deer
tick) & Rocky Mountain Spotted
Fever (wood or dog tick).
Centipedes & Millipedes
• many segments
• antennae
• simple eyes
• live on land in moist areas
• make nests and stay with eggs until
they hatch
Centipedes
• One pair of jointed leg per body
segment. Flattened body.
• Carnivorous & possess
venomous claws.
• Quick moving.
• 15-181 segments (always odd)
Millipedes
• Round bodies with 2 pairs of legs per
body segment.
• Possibly over 100 segments
• Feed on dead & decaying plant matter
• Roll up in a ball when disturbed.
• Some can expel cyanide gas or
unpleasant chemicals as a defense
mechanism.