protein and chitin
stiffened cuticle of arthropods
protection
function of hardened exoskeleton
muscle
what attachments can be found on hardened exoskeleton
sequence of molts
what is necessary to allow for growth in arthropods?
reduction of coelom
what resulted in loss of hydrostatic skeleton function?
extensions of jointed segments
what became appendages in arthropods?
yes
is arthropoda a diverse phylum?
1,100,000
how many species of arthropods recorded to date?
precambrian period
when does the fossil history date to?
hemocoel
name for arthropod open system of sinuses
exoskeleton
made of cuticle and is highly protective, jointed, and flexible so as to provide mobility
procuticle
inner, thick exoskeleton layer
epicuticle
outer, thin exoskeleton layer
they have mandibles
why are the groups myrlapoda, crustacea and hexapoda grouped together phylogenetically?
waxes
found on the outermost layer of the epicuticle to reduce water loss
sclerotization
chemical linking that stabilizes and hardens protein layers
exocuticle, endocuticle
\n Procuticle has an ______ secreted before a molt and an \n _______ secreted after molting.
50
percent chitin in insect procuticle
60-80
percent chitin in crustacean procuticle
makes it harder
what does more chitin do to an exoskeleton?
appendages
often differentiated and highly specialized for division of labor
segmentation and apendages
allow for efficient arthropod locomotion
to avoid intraspecific competitions
why do larvae and adults feed on different organisms and occupy different habitats?
tagmata
term for body regions in chelicerates
cephalothorax and an abdomen
two main body regions of chelicerates
no
do chelicerates have mandibles?
predaceous
nutrition of most arachnids
cephalothorax
which body region holds the 4 pairs of legs of chelicerates?
reproductive and respiratory systems
what does the chelicerate abdoman house?
pedipalps
modified, sometimes elaborately, for sperm transfer in males
digestive enzymes
Arachnids feed by releasing ________ over or into their prey and then sucking the fluids out
pedicel
small structure that joins cephalothorax and abdoman in spiders
book lungs
parallel air pockets extending into blood-filled chambers used for breathing in spiders
8
how many eyes in spiders
cuticular mechanoreceptors
Covers the legs of spiders and can detect air currents, web vibrations, and other stimuli. Help with awareness of environment due to poor vision
spinnerets
contain hundreds of microscopic tubes that run to abdominal silk glands
scleroprotein
liquid web secretion that hardens as it is extruded
at night
when do scorpions typically feed
pecten
used in scorpions to sense vibrations of the ground
pedipalps
modified into pincher structures in scorpions
spermatophore
placed into ground by male scorpion and female is dragged on top to deposit sperm
viviparous
term for scorpions meaning females brood their young \n within their reproductive tract
no
is the harvestman pedicel narrow?
order opiliones or harvestmen
also called daddy longlegs
penis, direct
unlike other aracnids, harvestmen have ____ for ______ sperm transfer in reproduction.
parasitic
what nutrition do most mites and ticks have during at least one life stage
capitulum
\n Name for mite and tick mouthparts on tip of the anterior
chelicerae
help pierce, tear, or grip food; found on each side of mite/tick
4
how many pairs of legs in adult mites/ticks
6, 8
When mite/tick egg hatches, it releases a ___________ legged larva which then forms_ ________ legged nymphal stages.
ixodes
tick species that carries lyme disease
carnivore
centipede nutrition
venom claws
how do centipedes kill prey?
pair of jointed legs
what does each segment of a centipede (except behind head and last 2) have?
sensory
what function does the longer last pair of centipede legs serve?
spiracles
in each somite of a centipede to allow air to diffuse through branched air tubes of the tracheae
decayed plant matter
what do millipedes typically eat
2
how many pairs of legs on each adult millipede abdominal section?
1
how many pairs of legs per segment in larval millipedes?
exoskeleton, efficient locomotion, developed sense organs, complex behavior, air piped directly to cells, diverse resource use through metamorphosis
why are arthropods so diverse and abundant?
malpighian tubes
used in arachnid excretion
maxilliped
feeding appendage modified from thoracic limb
protopod (coxa and basis), exopd, endopod
parts a maxilliped