ecdysozoans; arthropods Flashcards
1
Q
major roles of arthropods
A
- food chains; predation, prey, parasites, symbionts
- pollinators
- decomposers, scavengers
2
Q
major factors in the success of arthropods
A
- diverse
- adaptable body plan
- ability to thrive in range of environments
- body segmented; linear blocks allowing greater control of body regions and specialization of regions
- segments fused allowing even greater control of body regions and specialization (head, thorax, abdomen)
- exoskeleton w jointed appendages
3
Q
tagmatization/ tagmosis
A
- fusion of segments to produce super-segments; tagmata
allowed specialization of body from and function and specialization of appendages; allowed evolution from worm-like organisms
4
Q
arthropod features
A
- exoskeleton
- segmentation
- tagmata
- appendages
- respiratory structures
- circulatory system
5
Q
types of tagmata combinations
A
- head, thorax, abdomen
- head, trunk
- cephalothorax, absomen
6
Q
appendages
A
- tool for every purpose (mobility, sensing, feeding, reproduction)
7
Q
respiratory structures
A
gills, spiracles tracheae, book lungs
8
Q
circulatory system
A
- open (haemocoel)
- ventral nervous system
- complex excretory system
- sexual reproduction
9
Q
ecdysis
A
shedding exoskeleton
10
Q
exoskeleton made of
A
protein and chitin
11
Q
exoskeleton function
A
- physical, physiological protection, muscle attachment, supports body
- but must moult to grow
- temporary vulnerability and energetically expensive
12
Q
2 living groups of arthropods based on mouthpart organization
A
- chelicerates: chelicerae for grasping, often fang-like or pincers
- mandibulates; mandibles; for chewing
13
Q
chelicerates body
A
- simple body; cephalothorax and abdomen
14
Q
chelicerates mouthparts
A
- chelicerae; paired feeding appendages modified into fangs (spiders) or pincers
- pedipalps; aka palps, feeding or sensory
15
Q
do chelicerates have antennae
A
no true antennae
16
Q
chelicerates eyes
A
up to 8 single lens eyes
17
Q
how many legs do chelicerates have
A
8 legs (4 pairs)
18
Q
what are 4 examples of arachnids (chelicerates)
A
spiders, scorpions, ticks, mites
19
Q
mouthparts of a tick (arachnid, chelicerae)
A
- Developed secondary structure the hypostome (looks like xmas tree in middle of chelicerae) locks in place and is like a sucking straw
- Spikes on chelicerae are pedipalps (aka palps)
20
Q
mouth parts of a spider
(arachnid, chelicerae)
A
- Chelicerae bear fangs and teeth; teeth along inner margin
- Saliva has venom and digestive enzymes
21
Q
ticks (acarines)
arachnids, chelicerae, arthropods, ecysozoans
A
- external parasites of mammals, birds and reptiles
22
Q
how many hosts do ticks have
arachnids, chelicerae, arthropods, ecysozoans
A
1, 2 or 3
23
Q
what do ticks eat and how big can they get
arachnids, chelicerae, arthropods, ecysozoans
A
- heavy blood feeders; female ticks engorge; body size increases up to 100x
24
Q
what assists in tick feeding
arachnids, chelicerae, arthropods, ecysozoans
A
- saliva
- secrete neurotoxins
- therefore ticks can act as vectors of disease causing microorganisms
25
effects of ticks
arachnids, chelicerae, arthropods, ecysozoans
- spread disease causing micro-organisms as vectors
- blood loss
- skin damage
26
cattle tick lifecycle
arachnids, chelicerae, arthropods, ecysozoans
- rhipicephalus (boophilus australis)
- Engorged female drops of host and lays around 300 eggs into environment and dies
- Eggs develop; up to 2 months in summers, up to 7 months in winter
- Larva quest; climb up grass, front legs up waiting for bovine to walk past, wave legs to try and catch on hair
- Sit around shoulder/ neck region
- Will molt on host → nymph, molt again → adult
27
why is it so hard to remove a feeding tick
arachnids, chelicerae, arthropods, ecysozoans
- slicing chelicerae
- denticulate toothed hypostome and also adhesive cement in some species
- backwards facing spikes
28
mites
arachnids, chelicerae, arthropods, ecysozoans
- like tiny ticks
- most free living
- ectoparasitic species
29
are most mites parasitic
arachnids, chelicerae, arthropods, ecysozoans
no, most free living
30
major example of mites
- the scabies mite
- live and burrows on skin
- egg to adult on one host and transmission predominantly by contact
- cause mange; condition associated w severe dermatitis
- mange characterized by hair loss, scabs, keratinized skin w mites found in skin scraping
31
what do the mandibulates include
insecta (hexapoda)
32
mandibulates
- vast majority of species
- all environments
- many forms
33
mandibulates, insecta (hexapoda) what kind is the most abundant
beetles
34
insecta/ hexapoda (mandibulates) bodies
3 tagmata; head thorax and abdomen
35
mandibulates insecta (hexapoda)
thorax has how many pairs of legs
3 pairs of legs, sometimes 2 pairs of wings
36
why are insecta (hexapods) champions of terresterial environment
mandibulates
- size
- exoskeleton
- excretory system
- advanced respiratory system
- advanced sensory system
- internal fertilization
-resistant eggs
37
insecta (hexapods) exoskeleton
mandibulates
provides protection against environment
- jointed, hardened locomotory appendages; legs and wings hence greater dispersion
38
insecta (hexapods) excretory system
mandibulates
composed of tubules that pass through body, extract water from wastes, nitrogen waste excreted as uric acid
39
insecta (hexapods) advanced respiratory system
mandibulates
- spiracles open to outside
- tracheae (tubules) ramify through body
- direct oxygen supply to tissues
40
insecta (hexapods) advanced sensory system
mandibulates
- antennae compound eyes
- also cerci of cockroaches
41
insect evolution is associated with
plant evolution
42
hexapods arrived not long after
plants colonized terrestrial environment
43
looking at evolution of insects; first type we look at that are primitively wingless with mostly simple mouths are called:
insecta (hexapods) mandibulates
apterygotes
44
what is a modern day apterygote
insecta (hexapods) mandibulates
collembola- springtails
thysanura- silverfish
45
what group in the evolution of insects did we see the evolution of wings
insecta (hexapods) mandibulates
palaeoptera
- 350 MYA
- simple insects w simple development
- wings of these insects did not fold over abdomen
46
in the group palaeoptera the wings did not
insecta (hexapods) mandibulates
fold over abdomen
47
modern day example of palaeoptera
insecta (hexapods) mandibulates
dragon flies and may flies
48
after palaoptera, we saw orthopteroida, what was developed in this group
insecta (hexapods) mandibulates
development of wings that fold over abdomen
49
some examples of orthopteroida; insects w wings that fold over abdomen
insecta (hexapods) mandibulates
- grasshoppers
- praying mantis
- stick insects
- cockroaches
50
after the orthopteroida we saw evolution of two lineages
1) those that maintain simple development (hemimetabolous)
2) those with complete metamorphosis (holometabolous)
51
hemimetabolous imeans what and includes what group in evolution
insecta (hexapods) mandibulates
those that maintain simple development
- hemipteroida
52
hemimetabolous life cycle consists of
- egg
- juvenile form (nymph) that look like adults but lack wings and not sexually mature
- juveniles moult to grow
- adults, often have wings but not always, sexual maturity
53
nymph
juvenile form that look like adults but lack wings and not sexually mature (hemimetabolous)
54
examples of hemiptera
- lice, bugs, aphids, bed bugs, kissing bugs
- mostly plant feeders but some parasitic
55
important disease caused by parasitic hemipteroida
insecta (hexapods) mandibulates
- chagas disease transmitted by kissing bug and assassin bug caused by a trypanosome (flagellate)
56
what 3 groups have true metamorphosis (holometabolous development)
insecta (hexapods) mandibulates
- neuropteroida
- hymenopteroida
- panorpoida
(don't worry about the differences between the groups)
57
holometabolous development
insecta (hexapods) mandibulates
- Larva v different from adult form
- Larva specializes in feeding, growing and developing
- Larva molts to grow, when fully developed it ceases feeding and then pupates
- Pupa is a transitional phase; internally larva develops to sexual adult
- Adult specializes in reproduction, dispersion, egg laying, can be feeding or non feeding
- Classic ex is butterfly: larva is caterpillar, pupa is cocoon, adult is butterfly
58
advantages of true metamorphosis (holometabolous)
insecta (hexapods) mandibulates
- Major advantage; allows partitioning of life cycle
- Allows adults to occupy a completely different habitat from larvae
- Enables larvae and adults to exploit different food resources
- Metamorphosis allows insects to escape from temporary habitats ex if larva lives in pond but then bond dries up it will still survive (before conditions become unfavorable for survival)
59
3 main groups of insects of veterinary significance
insects, hexapods, mandibulates
lice, fleas, flies
60
lice
insects, hexapods, mandibulates
- permanent ectoparasites
- small, wingless dorso-ventrally flattened body
- hooked tarsi (terminal segments of legs) grip hair
- host specific; different species on every species of domestic animal and humans and most birds and mammals
61
two main types of lice
insects, hexapods, mandibulates
- chewing lice (mallophaga) mammals, birds, feed on skin
- sucking lice (anoplura) mammals only, feed on blood
62
how do lice cause harm to house
M= mallophaga= chewing lice
A= anoplura= sucking lice
insects, hexapods, mandibulates
- irritation, skin damage (M and A)
- anaemia from blood loss (A and M)
- vectors of disease organisms (A)
- intermediate hosts of parasites; tapeworms (M)
63
lice life cycle
insects, hexapods, mandibulates
- Egg laid of feather of hair, glued to shaft
- Hatch to be 1st nymph → molt to second nymph and again to 3rd nymph
- Then molt to adult male or female
64
sheep body louse
insects, hexapods, mandibulates
feeds on skin, wool, but causes intense irritation
65
hematopinus
insects, hexapods, mandibulates
blood sucking louse of pigs and ruminants
66
head/body louse pediculus humanus P. capitis
insects, hexapods, mandibulates
two species of human lice
vectors of typhus
67
phthirus pubic
insects, hexapods, mandibulates
pubic louse (crabs)
sexual transmission
68
fleas
insects, hexapods, mandibulates
- non permanent extoparasites; small laterally compressed adults
- muscular hing legs
69
fleas hosts
insects, hexapods, mandibulates
birds and mammals
70
flea feeding
insects, hexapods, mandibulates
blood feeder; have sucking mouthparts adapted to piercing skin and feeding on blood
71
flea eggs
insects, hexapods, mandibulates
laid on host or in nest of host (including kennels, blankets, cracks in floor, couches)
72
fleas larva
insects, hexapods, mandibulates
- detritus feeder, not on hosts,
- chewing mouthing parts
- in cats and dog flea larva feed on adult flea feces, gain essential nutrition form flood in feces
73
flea larva vs adult mouthparts
insects, hexapods, mandibulates
- larva; chewing mouthparts
- adult; sucking mouthparts
74
how do fleas cause harm to host
insects, hexapods, mandibulates
- direct harm; flea bite allergy (hypersensitivity), blood loss, especially anaemia in kittens, pups and aged animals
- vector; bacteria (plague, cat scratch disease; bartonella), virus (myxomatosis)
- intermediate host; fleas host to "cucumber" tapeworm of dogs and cats (dipylidium caninum)
75
life cycle of cat flea; ctenocephalides felis
insects, hexapods, mandibulates
- holometabolous: complete metamorphosis; larva then pupa then adult
- Adult; lays eggs on host
- Off host; Eggs nutritive source, derived from parents during egg formation
- Hatch to larvae, in bedding, carpets, soils, nests, feed on detritus feces of adults
- Pupa; lives off energy is stored when it was larva
- Then adult flea back on host
76
flies and mosquitoes
insects, hexapods, mandibulates
- important insects in relation to animal and human disease
77
types of adult flies
- filth flies; house and blow flies
- blood sucking adults; blood loss (stable flies, horse flight) and vectors of disease (mosquitos, tsetse fly)
78
diseases associated mosquitos and tsetse fly
- tsetse fly; trypanosomiasis
- mosquitos; malaria and heart worm
79
larval stages of flies
- decomposition of bodies; blow fly, flesh fly maggots
- strike flies; myiasis, where maggots grow on living tissue of animals; strike flies
- bot flies; maggots grow in internal organs
80
crustaceans
mandibulates
- dominant aquatic arthropods
- some moist terrestrial (isopods)
- extensively specialized appendages
- many small crustaceans important in plankton?
81
plankton
passive drifters, weak swimmers, most small, include larval forms of larger crustaceans, NB aquatic food chains
82
copepods
crustacean, mandibulates
- important group of crustaceans
- important food source in aquatic systems
- some copepods are predatory
- mesocyclops has been used to control dengue mosquito
- can be parasitic on fish
83
what tagmata do crustaceans typically have
cephalothorax and abdomen
