Exam 1: Arthropods & ticks

Question 1

members of populations or groups of organisms that actually or potentially interbreed in nature and produce viable, fertile offspring

Answer 1

biological species

Question 2

a group of closely related species that look almost identical but different genetically, behavior, life history

Answer 2

cryptic species complex

ex. house mosquito complex

Question 3

males and females have distinctly different appearances

Answer 3

sexual dimorphism

ex. antennae of mosquitoes, eye size of many flies

Question 4

what are the visible characteristics of phylum arthropoda

Answer 4

a. segmented body and appendages (legs, antennae)

b. hard external skeleton of chitin - tough, flexible polysaccharide (sugar) containing nitrogen

Question 5

Name the 5 major groups of arthropod

Answer 5

1. Crustacea - pillbugs, crayfish, shrimp
2. Arachnida - ticks, mites, spiders
3. Chilopoda - centipedes
4. Diplopoda - millipedes
5. Insecta - flies, lice, etc.

Question 6

2 pairs of antennae, 2 main body regions, 5 pairs walking legs, scavengers, some predators, mostly marine aquatic

Answer 6

crustacea

Question 7

No antennae, 4 pairs of walking legs, 2 main body regions (may look like 1), mostly terrestrial - predators, parasites, herbivores, etc.

Answer 7

arachnida

Question 8

1 pair antennae, 2 body regions - head and trunk with many segments, 1 pair appendages per segment
1st segment - fangs, others are legs, flattened body - long legs, terrestrial predators - venomous bite

Answer 8

chilopoda (centipedes)

Question 9

1 pair antennae, 2 body regions - head and trunk with many segments, 2 pair short legs per trunk segment, cylindrical body, terrestrial herbivores, scavengers

Answer 9

diplopoda (millipedes)

Question 10

1 pair antennae, 3 main body regions, 3 pairs of legs, may have wings, mostly terrestrial - many feeding strategies

Answer 10

insecta

Question 11

reasons for arthropod success

Answer 11

~many have complete metamorphosis
~high repro rate w/ 100’s - 1000’s of young per female
~most species w/ winged adults - dispersal
~small
~short life cycles
~high genetic diversity among individuals - rapidly adaptable

Question 12

what is & types of metamorphosis

Answer 12

change in form

gradual and complete

Question 13

gradual metamorphosis

Answer 13

egg, nymph, adult

most arthropods, some insects

Question 14

complete metamorphosis

Answer 14

egg, larva, pupa, adult

most insects

Question 15

advantages of exoskeleton

Answer 15

protection, strength (muscle support and leverage), conserve water

Question 16

disadvantages of exoskeleton

Answer 16

heavy (limits growth and body size), reduced mobility, very limited damage repair, hard to detect external stimuli

Question 17

molting

Answer 17

shed old, outgrown covering

old exoskeleton splits along lines of weakness, use blood pressure or air to expand before hardening

Question 18

what controls metamorphosis

Answer 18

hormones - molting hormone tells the insect when to molt and grow

Question 19

the level of jubenile hormone in blood determines

Answer 19

stage after a molt

immature or adult insect becomes adult if the JH level is below a certain value

Question 20

how many times does a species molt?

Answer 20

4-8; more if under stress

Question 21

instar is a term for

Answer 21

an immature

dangerous time

Question 22

how do insects detect stimuli

Answer 22

palps (taste buds) - often final step in host selection
compound eyes- many lenses- large eyes and many small lenses = better vision
touch-body hairs
antennae (nose) - chemical odors - airborne or contact, on host, on each other; large antennae usually = greater reliance on chemicals/odors

Question 23

argasidae

Answer 23

soft ticks; no hard plate on back; most species feed on birds; less important than hard

Question 24

ixodidae

Answer 24

hard ticks;sclerotized plate back covers entire back of male, part of back of female; mostly mammal hosts

Question 25

ticks classification

Answer 25

phylum: arthropoda class: arachnida order: acarina family: argasidae or ixodidae

Question 26

list some tick impacts

Answer 26

parasites - all species are blood feeders stress to host - irritation, anemia allergic reactions to injected substances by host - many substances injected during feeding: vasodilators, anti-coagulants, pain suppressors feeding wounds - maggot attack, secondary infections; transfer pathogens (vectors) - 2nd to mosquitos anemia, tick paralysis

Question 27

ticks develop through what type of metamorphosis

Answer 27

gradual

Question 28

tick life strategy

Answer 28

``` high fecundity (fertility) offsets low survival thousands of eggs produced by a female but mortality through development is high ```

Question 29

life stages of the tick

Answer 29

egg and 3 life stages - larva (seed tick) 6 legs; nymph 8 legs; adult 8 legs each immature stage has a blood meal, digests it and molts

Question 30

how much time does the tick spend off host

Answer 30

95+ % of its life is on ground

Question 31

tick survival

Answer 31

find shelter from direct sun - move to best microenvironment absorb water form air (mouthparts) if humidity is high enough find host and mate

Question 32

key environmental elements for ticks

Answer 32

temp, rainfall, protection

Question 33

1 host tick

Answer 33

larva finds host - entire life cycle completed on that host engorged female drops off to lay eggs

Question 34

3 host tick

Answer 34

each active stage independently finds a host - may be different species each time

Question 35

main factors in order for tick to finding hosts

Answer 35

CO2 vibration of substrate from host movement body heat host-produced substances-constituents of sweat and skin lipids - HOST SPECIFICITY - often in final decision vision-very limited

Question 36

how to sample for ticks

Answer 36

tick traps, host traps, flagging

Question 37

where are the life stages of ticks distributed

Answer 37

larvae - clumped where egg mass was deposited nymphs & adults - single and more dispersed depending where they drop; may be clumped along host trails or bedding sites

Question 38

how do ticks attach

Answer 38

cut skin and insert hypostome and anchor with 'cement'

Question 39

what prevents blood clots when ticks attach

Answer 39

saliva

Question 40

how long does attachment occur for disease transfer

Answer 40

24-36 hours

Question 41

when do ticks detach and drop?

Answer 41

where chances of finding another host are high

Question 42

ticks usually drop off

Answer 42

when hosts are inactive - after nightfall or during day for nocturnally active hosts

Question 43

reactions to saliva, capillary dilators, and anticoagulants are related to

Answer 43

tick bite allergies

Question 44

red meat allergy is associated with what kind of tick

Answer 44

lone star

Question 45

red meat allergy occurs

Answer 45

in susceptible individuals after multiple tick bites

Question 46

what is the suspected cause of red meat allergy

Answer 46

antibodies to a sugar (alpha-gal) produced in persons blood after multiple LST bites

Question 47

what are the characteristics of an efficient disease vector

Answer 47

obligate blood feeders feed several times feel slowly ( time to aquire a pathogen ) long life protect and take pathogen to a susceptible host pathogens may multiply in vector

Question 48

tick removal

Answer 48

grab at skin and use steady pull | most important factors in avoiding tick-borne diseases

Question 49

common tick that is relatively rare in KY

Answer 49

black legged tick

Question 50

common tick-most important disease vector

Answer 50

american dog tick

Question 51

important nuisance tick

Answer 51

lone star tick

Question 52

common tick that is in kennels - only tick that can live and multiply indoors

Answer 52

brown dog tick

Question 53

tick borne disease, one of several bacterial diseases that affect humans and animals but rare

Answer 53

Erlichiosis

Question 54

primary vector and symptoms of erlichiosis

Answer 54

lone star tick | headache, feer, muscle aches within 1-2 weeks of bite

Question 55

this tick is the vector of rocky mountain fever

Answer 55

american dog tick

Question 56

what intracellular bacterium causes rocky mountain fever?

Answer 56

rickettsia

Question 57

reservoirs of rocky mtn spotted fever

Answer 57

opossums, rabbits, chipmunks, squirrels, rats and mice

Question 58

rickettsia becomes virulent only after how long of a time period of tick attachment?

Answer 58

>10hours

Question 59

vector of lyme disease

Answer 59

blacklegged tick

Question 60

bacterium of lyme disease

Answer 60

borrelia burgdorferi

Question 61

reservoirs of lyme disease

Answer 61

mostly white-footed mouse, shrews, chipmunks

Question 62

where are blacklegged ticks seen

Answer 62

eastern and south and north central us

Question 63

what are 3 main tick management practices

Answer 63

habitat management reduce immigration acaricide applications