Ch 18: Arthropoda Intro

Question 1

5 subgroups/phyla

Answer 1

• crustaceans
• trilobites
• chelicerata
• myriapods
• hexapods

Question 2

6 body features

Answer 2

• segmented body, some fused
• hardened chitinous exoskeleton
• jointed appendages, specialized
• well-cephalized w/ well-developed sensory organs
• no motile cilia on cells
• striated muscles

Question 3

3 functs of exoskeleton

Answer 3

• defense
• muscle attachment
• water-proofing

Question 4

7 funct of appendages

Answer 4

• walking/jumping
• swimming
• prey capture and defense
• feeding
• olfaction
• tactile
• copulation

Question 5

muscles (2)

Answer 5

• highly innervated for fast response

- a single neuron may innervate many fibers

Question 6

4 reasons for arthropod success

Answer 6

• adaptability of body plan
• small size
• rapid generation time
• innovations like flight and silk

Question 7

adaptability of body plan

Answer 7

• body regions and appendages can be specialized

- waterproof ability

Question 8

small size adv (2)

Answer 8

• many open niches

- don’t need many resources to survive

Question 9

rapid generation time allows (2)

Answer 9

• rapid exploitation of new habitats

- evolution can occur quickly

Question 10

4 benefits to flight

Answer 10

• more food sources
• better access to mates
• more efficient dispersal
• escape predators

Question 11

5 features of the exoskeleton/cuticle

Answer 11

• non-living
• makes up most external structures
• carries internal ridges for muscle attachment
• a series of plates connected by areas of thin cuticle and a rubbery protein called resilin
• layered

Question 12

3 layers of the exoskeleton

Answer 12

• outermost
• thin
• waxy

Question 13

endo and exocuticle contain (3)

Answer 13

• chitin
• proteins
• CaCO3 in crustaceans

Question 14

sclerotized

Answer 14

darker, harder, more chitin and sclerotin

Question 15

molting allows for (3)

Answer 15

• growth
• repair
• metamorphosis

Question 16

which cuticle get recycled during metamorphosis?

Answer 16

endocuticle

Question 17

which cells create new layers

Answer 17

epithelial

Question 18

ecdysis

Answer 18

old epi and exocuticle break along ecdysal lines and shed

Question 19

ecdysal lines

Answer 19

non-sclerotized weak points

Question 20

exuvia

Answer 20

old epi and exocuticle

Question 21

how does ecdysis begin

Answer 21

expanding body via air, w, w/ specialized muscles

Question 22

what must the outer layer do after molting

Answer 22

sclerotize

Question 23

what is molting controlled by

Answer 23

hormones

Question 24

3 things that can stimulate molting

Answer 24

• temp
• day length
• feeding/stretch receptors

Question 25

5 steps to molt

Answer 25

- stimulus - impulses reach brain - neurosensory cells prod neurohormones - molting glands stimulated prod molting hormone - epidermis and other target cells affected

Question 26

high levels of JH

Answer 26

molt to another juvi

Question 27

low lvls of JH

Answer 27

molt to pupa/adult

Question 28

3 feat of tagmata

Answer 28

- made of several ancestral segments - ancestral appendages may be retained or modified - tagmata specialized

Question 29

3 tagmata in insects

Answer 29

- head - thorax - abdomen

Question 30

tagmata in myriapods (2)

Answer 30

- head | - trunk

Question 31

2 tagmata in crustaceans

Answer 31

- cephalothorax | - abdomen

Question 32

2 tagmata in spiders

Answer 32

- cephalothorax | - abdomen

Question 33

head funct

Answer 33

eating, gathering sensory info

Question 34

5 types of appendages that can be on the head

Answer 34

- mandibles - antennae - maxillae - chelicerae - pedipalps

Question 35

types of eyes

Answer 35

ocelli, compound

Question 36

3 feat of the thorax

Answer 36

- carries walking appendages - carries wings - muscular

Question 37

2 feat of abdomen

Answer 37

- contains viscera | - muscles for swimming, digging

Question 38

nervous system (2)

Answer 38

- anterior brain connects to a subesophageal ganglion | - pair of ventral nerve cords w/ segmental ganglia and multiple nerve strands

Question 39

circ open or closed?

Answer 39

open

Question 40

3 feat circ

Answer 40

- dorsal heart pumps hemolymph anteriorly - holes along heart sides (ostia) - hemolymph flows back thru hemocoel

Question 41

4 hemolymph funct

Answer 41

- hydraulic pres - transport and storage - protection - temp regulation

Question 42

do insects use their hemolynph to transport/store O2 and CO2?

Answer 42

no

Question 43

aquatic spp have

Answer 43

gills

Question 44

terrestrial spp have (2)

Answer 44

trachea or book lungs

Question 45

the tracheal system is

Answer 45

an internal duct system

Question 46

the tracheal ducts are lined by

Answer 46

cuticle

Question 47

spiracles

Answer 47

openings to outside from the tracheal ducts

Question 48

what do the tracheae open into

Answer 48

air sacs

Question 49

air movement in the tracheal ducts in incd by

Answer 49

abdominal pumping

Question 50

book lungs are present in

Answer 50

spiders

Question 51

book lungs are a

Answer 51

moist internal space for gas exchange into hemolymph w/ layered circ system extensions

Question 52

gut

Answer 52

one way

Question 53

cuticular teeth

Answer 53

for mechanical digestion partway down

Question 54

aquatic spp excrete

Answer 54

NH3 - needs to be diluted, which requires lots of w

Question 55

insects/myriapods excrete

Answer 55

uric acid, costs little w but costs C and E

Question 56

arachnids excrete

Answer 56

guanine

Question 57

malpighian tubules (3)

Answer 57

- empty into the intestines - filter the hemolymph - excrete into the hind gut

Question 58

insect frass

Answer 58

nitrogenous wastes and feces