lecture 6 arthropoda 1: gen characteristics, crustatceans, millipedes, centipedes, spiders Flashcards
what does the phylum arthropoda mean in latin
arthro = joint poda = feet
what kind of symmetry do arthropods have
bilateral
what kind of coelomates are arthropods
coelomates
what kind of skeleton do arthropods have
exoskeleton
what are arthropods skeletons made of
chitin and proteins
segregated by the epidermis
benefits of the exoskeleton
protects you and prevents water loss
independence from environment
more efficient locomotion
drawbacks of an exoskeleton
its makes it difficult to grow and gas exchange difficult.
limited movement
four stages of moulting
intermoult
premoult
moult
post moult
how does moulting happen
first the skeleton seperates from the cells, then a new cuticle forms
new skin has room for expansion
what type of body do arthropods have
segmented
what kind of legs do arthropods have
paired, jointed appendages
what are the parts of the body
head
thorax
abdoment
what does the thorax carry
the legs
whats in the abdomen
most of the internal organs
how do small arthropods have gas exchange
through the skin, restricted to damp areas
how do aquatic crustations have gas exchange
gills Blood to supply to filaments O2 diffise from water to blood
how do terrestrial scorpions & spiders have gas exchance
book lungs In terrestrial need to take O2 from air – 2 solutions – book lung – big spiders and scorpions is inside the body air flows in through a pair of holes on the abdomen and diffuses across membranes in these plaques.
how do terrestrial insects and millipedes have gas exchange
tracheae
Many insects, small spiders (can have both) and millipedes – system of tubes getting narrower and narrower as get deeper in the body – tubes also contain fluid O2 diffuses, but no blood – tiny tubes go right into the muscles and organs.
what do mechanoreceptors sense
touch and vibrations
what do chemo receptors sense
smell and taste
what do photoreceptors sense
ocelli & compound eyes
light
what kind of eyes do spiders have
simple eyes with a single lense but up to 8
what type of sexual reproduction do arthropods have
sexual reproduction with seperate sexes
external (horseshoe crab)
internal
how do horseshoe crabs mate
female lays in hole on beach and male releases sperm over the eggs.
what are the arthropod subphylums
trilobitomorpha pycnogonida crustacea myriapoda chelicerata hexapoda
fun fact about trilobitomorpha
all speices are currently extinct
fun fact about pycnogonida
sea spiders
all marine species, sometimes joined with the spiders
what families are included in the subphylum crustacea
shrimp, crabs, copepods, waterfleas
all aquatic except woodlice
what cuticles do crustacea have
epicuticle and protocuticle with calcium carbonate
how do crustacea have gas exchange
gills
crustacea gill speciality
Gills can have very developed sensory organs, many associated with floor – walking or burrowing.
what kind of vision do crustacea have
compound and simple eye
how do crustacea reproduce
seperate sexes, internal fertelisation
what kind of larva do crustaceas have
nauplious larva
what order are woodlice
isoptera
what do crustaceans typically have 5 of
pairs of marching legs
what do crustateans typically have fused
head and thorax
what are some of the crustaceans transformations of
the mouthparts
how is sperm transfered in crustaceans
using first abdominal segment appendages (gonopods) inserted into female genital opening into seminal recepticle
what does subphylum myriapoda mean in latin
myria 10,000
poda = feet
what organisms are myriapods
milipedes & centipedes
what kind od cuticle do they have
epicuticle waxy waterproof
how do myriapods have gas exchange
tracheae
what kind of eyes do myriapods have
simple eyes
dark environment
how do myriapods reproduce
seperate sexes indirect sperm transfere with spermatophore
what are the myriapoda body parts
head with one anntena and mandibles
body with many segments
jointed appendages
millipede: no. legs per segment
2 pairs
centipede: no. legs per segment
1 pair
what class are milipedes
diplopoda
what class are centipedes
chilopoda
what does the subphylum chelicerata mean in latin
chelice = claws
who are some chelicerats
scorpians, spiders, harvestmen, ticks
all terrestrial except horseshoe crabs
how do chelicerates exchange gas
gills, book lungs, tracheae
what kind of eyes do chelicerates have
simple and compound
how do chelicerates reproduce
seperare sexes indirect sperm transfere with spermatophore
what are the chelicerata body parts
cephalothorax
4 pairs of marching legs
no antenna
chelicera and pedipalps(one pair of each)
how do scorpians shag
complex courtship
females have a tendancy to eat the males
lasts 45 mins
how do harvestmen shag
for 38 mins
how do spiders fuck
– sucks up sperm/silk into his pedipalp and inserts this into the females genital opening
what is the species name for harvestmen
opiliones
how do chelicerata do parental care
wolf spider and scorpions carry young on thier backs to protect them and provide food
what class and orders are in chelicerata
class: arachnida
order: araneae
opiliones
acarina
main characterisitic of arthropods
exoskelton segmented body well defines head jointed appendages respratory organs sensory organs
how mang pairs of legs to isopods have
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