W8&9- Phylum Arthropoda. Class Arachnida

Question 1

Phylum Arthropoda characteristics

Answer 1

• Segmented body covered by chitin exoskeleton=protection +provides muscle attachment.
• Arthropods molt because their
  exoskeletons don’t grow with them.
• Open circulatory systems w/ dorsal heart which collects blood from the body cavity+ pumps it back into the body cavity.
• nerve system = developed sense organs. ganglia connected to bundle of nerve.
• Jointed appendages – antennae, mouthparts and walking legs.

Question 2

Phylum Arthropoda morphology

Answer 2

Bilateral symmetry helps easy movement body: head, thorax & abdomen. each segment= pair of legs
triploblastic- end, miso, ectoderm
coelomates- body cavity made of blood haemocoel.

Question 3

what is indirect development?

what is direct development?

Answer 3

Includes larval stage
metamorphosis= multiple larval stages

No larval stage
young ones = smaller version of adults

Question 4

Class Crustacea morphology

e.g lobster, crab, crayfish, prawns

Answer 4

most are free living, but some are sessile (immobile)
consists of cephalothorax (5 segments) and abdomen.
- in cephalothorax first 2 segments= pair of Antenne, other 3 have appendages for mechanical processing of food. pair of mandibles and two pairs of Maxallae also has pair of eyes
- thorax+ abdomen:

Question 5

what parasites are Genus Cyclops intermediate host for?

Answer 5

Dracunculus (guinea worm) and Diphylloborthrium (fish tape worm)

Question 6

Genus Cyclops morphology

Answer 6

2–3mm, 1 black/red eye in middle of head. green/yellow in colour
ant part =broad, oval
post part= thinner
5 pairs of legs, 2 Antennae (used to grip female during mating).
female carry eggs in sacs+ multyply rapidly- have an imp role in food chain.
Male and female differ by antennae

Question 7

what does Genus Cyclops feed on

Daphnia pulex reproduction cycle

Answer 7

plankton/algae

alternating asexual + sexual phases (parthenogenesis).

Question 8

Class Arachnida characteristics

e.g spiders, scorpions, harvestmen, ticks and mites.

Answer 8

Almost all are terrestrial, some live in freshwater + marine environments as well.
- body= cephalothorax (7 fused cephalic+thoracic seg) and abdomen
- 8 legs= front pair of legs for
sensory function, legs adapted for locomotion + end w/ claw
Chelicerae= for grasping + tearing food apart, has venom
pedipalps = reproduction

Question 9

what is Order Araneae known as?

Answer 9

Spiders = air-breathing arthropods that have 8 legs and chelicerae w/ fangs that inject venom

Question 10

Order Araneae body

Answer 10

body= cephalothorax + abdomen. no antennae.
4 pairs of eyes on top of cephalothorax.
abdomens= appendages which are spinnerets that extrude silk
Fangs(chelicerae)- deliver venom to capture+ kill prey.

Question 11

Order Araneae nervous system

Answer 11

Concentrated in cephalothorax. Ganglia fused into a mass found below the brain, so cephalothorax is largely filled with nervous tissue.
No ganglion in abdomen

Question 12

Order Araneae respiration

Answer 12

Have book lungs/ tracheal system or both
2 pairs of book lungs filled w/ hemolymph(blood in invertebrates, occupying haemocoel),
openings on ventral surface of abdomen allow air to enter + diffuse oxygen
Trachea has openings, (spiracles)

Question 13

Order Araneae circulation

Answer 13

Open circulatory system (no blood/veins)
body filled with heamolymph, which is pumped through arteries by a heart into sinuses
spiders= coelomates(has body cavity), largely taken up by haemcoel= cavity that heamolymph runs through.
Heart located in abdomen = simple tube, surrounded by thin wall= Pericardium

Question 14

Order Araneae digestion

Answer 14

Digestion occurs internally + externally. Secrete digestive fluids onto prey from ducts on Chelicerae.
digestive fluids dissolve prey’s internal tissues. spider feeds by sucking the partially digestive fluids.
Midgut has many digestives ceca (pouches) that extra nutrients from food

Question 15

Order Araneae excretion

Answer 15

Convert nitrogenous waste to uric acid. malphigian tubules extract waste from blood in hemacoel and expel through anus

Question 16

what is Latrodectus

tredecimguttatus known as?

Answer 16

Mediterranean black

widow

Question 17

Latrodectus tredecimguttatus habitat

Answer 17

grasslands

Question 18

Latrodectus tredecimguttatus morphology

Answer 18

female: Has 13 red spots on dorsal abdomen
male: bright white spots and reddish dots in centre
Body = cephalothorax and abdomen
female: larger in size and have black abdomen
male: smaller and abdomen is elongated
6 pairs of appendages: chelicerae(upper jaws), pedipalps(lower jaw), 4 pairs of legs

Question 19

Latrodectus tredecimguttatus development

bite?

Answer 19

direct

Only female bite is dangerous as mail cannot penetrate the epidermis

Question 20

Order Scorpiones morphology

Answer 20

9-210mm// 2-25yrs
2 large pedipalps that end in pincer
8 legs, narrow segmented tail which ends with a stinger body= 5 segments bears stinger

Question 21

Order Scorpiones nervous system

Answer 21

CNS- brain + ventral nerve cord.

brain = 2 large ganglion that surrounds the oesophagus

Question 22

Order Scorpiones morphology

Answer 22

9-210mm // 2-25yrs
2 large pedipalps that end in pincer
8 legs, narrow segmented tail which ends with a stinger body= 5 segments bears stinger

Question 23

Order Scorpiones feeding

Answer 23

1) prey is at claw of pedipalps.+ stung
2) prey Brough to oral cavity. chelicerae wounds body
3) pharynx sucks fluid, saliva mixes with it.
4) partially digested food moved tp midgut. further digestion-enzymes
5) residue digested through anus

Question 24

Order Scorpiones excretion

Answer 24

2 pairs of Malpighian tubules attached to intestine. waste expelled through anus.
coxal gland- urine (bladder opening)

Question 25

Order Scorpiones circulation

Answer 25

open. tubular heart located dorsally. runs length of mesosoma

Question 26

Order Scorpiones respiration

Answer 26

4 pairs of book lungs- consists of many 'plates' stacked closely together. passive diffusion occurs

Question 27

Order Scorpiones reproductive

Answer 27

separate sexes, paired gonads. sperm enters female gonopore+ fertilisation is internal 1) male deposits sperm at site 2) male glides over female area 3) spermatophore enter female genetalia, it fertilises female 4) egg develops in ovary+ nourishes embryo- viviparous. young resembles adult

Question 28

Genus Euscorpius

Answer 28

4cm genus of scorpions, called small wood- scorpions species varies color (black w/ yellow-brown legs and darker sting. some w/ dark brown bodies, light brown venom has local effect found in gardens, forest, house N.Africa and Europe

Question 29

Genus Euscorpius

Answer 29

4cm genus of scorpions, called small wood- scorpions species varies color (black w/ yellow-brown legs and darker sting. some w/ dark brown bodies, light brown venom has local effect- causes local inflammatory reaction found in gardens, forest, house N.Africa and Europe

Question 30

Order Acari

Answer 30

Acari (or Acarina) = mites + | ticks.

Question 31

Order Acari body

Answer 31

segmented body: cephalothorax + abdomen. they are completely fused= radiosoma. 4 pairs of legs, some=fewer. mouth parts=adapted for biting, stinging or sucking. They breathe through tracheae, stigmata (small openings of the skin), intestines and the skin itself.

Question 32

Order Acari body

Answer 32

segmented body: cephalothorax + abdomen. they are completely fused= radiosoma. 4 pairs of legs, some=fewer. mouth parts=adapted for biting, stinging or sucking. has a calcified proboscis on base = hypostome

Question 33

Order Acari respiration

Answer 33

breathe through tracheae, stigmata (small openings of the skin), intestines and the skin itself.

Question 34

Order Acari reproduction

Answer 34

Separate sexes. sperm transferred to female indirectly | sperm can be deposited which is picked up by female. or sperm injected by chelicerae into female gonophore

Question 35

Order Acari ticks vs mites

Answer 35

``` Mites= 0.5-3mm ticks= 3-30mm ``` mites live on land or water Some species carry disease- producing microorganisms;. some are sgricultural pests, feeding on crops Mite body= soft and hairy. ticks live on land (woods, pasture). blood-sucking parasites carry disease producing microorganisms, which they transmit Tick body =leathery and hairless

Question 36

Order Acari gen life cycle

Answer 36

egg--> larva(max 2)--> nymph (max 3)--> adult. Development includes metamorphosis Larvae(6 legs) hatch from fertilised egg only has basic systems Larvae turned to Nymphs (8legs) after 3 molts. they have immature repro system. after 3 molts then becomes adult (8 legs)

Question 37

what is Sarcoptes scabiei known as

Answer 37

itch mite- skin parasite

Question 38

Sarcoptes scabiei cause

Answer 38

scabies (cutaneous ascariasis) severe itching and infections.it burrows into skin

Question 39

Sarcoptes scabiei transmission

Answer 39

Person to person contact – transfer of pregnant female. skin to skin contact

Question 40

Sarcoptes scabiei life cycle

Answer 40

Egg, Laragh, nymph, adult 1) Adult female deposit eggs as they borrow in skin. 2) eggs hatch into larva (6 legs). which migrates to skin surface+ burrows into molting pouches- often hair follicles. 3) larvae molts into nymph (8 legs), this then molts into bigger nymph and then adult. 4) Adult male mite penetrates molting pouch of female 5) impregnated female leave pouches looking for suitable location for permanent borrow. only mate once.

Question 41

Sarcoptes scabiei respiration

Answer 41

Lacks trachea and stigmata so uses entire body surface for respiration

Question 42

Sarcoptes scabiei morphology

Answer 42

female: 0.4mm male: 0.2mm, males do no burrow. body= round, ventrally flattened+ dorsally convex w/ 4 pairs of short legs. front legs and mouthparts can slice through skin. other legs have suckers to hold onto skin. NO eyes

Question 43

what are Genus Dermatophagoides known as? cause

Answer 43

house dust mites allergy

Question 44

Genus Dermatophagoides morphology diet

Answer 44

microscopic- 0.2-0.3mm Very small translucent body striated cuticle feeds on skin flakes

Question 45

Tick-borne diseases/ removal

Answer 45

First aid equals best way to remove tech – tweezers and disinfect wound. no tweezers, use gloves not bare hands. keep tick for inspection Tick-borne diseases are infections transmitted by ticks. eggs can get the infection from mother (trans-ovarian transfer) mouth parts has hooks which stay in skin Transmitted pathogens: rickettsia, bacteria, viruses and protozoa. Major tick-borne diseases: Lyme disease, Rocky Mountain spotted fever, relapsing fever, tularemia, tick-borne meningoencephalitis, Colorado tick fever, Crimean-Congo hemorrhagic fever, etc.

Question 46

what is Ixodes ricinus known as?

Answer 46

hard ticks

Question 47

Ixodes ricinus morphology

Answer 47

male: 2.4-2.8mm femle: 3.0-3.6mm Hard bodied tick 11 mm after bloodmeal cuticle impregnated w/ chitin.this form shield mouth parts- cuts skin+ good for blood sucking chelicerae + pedipals form proboscis. hypotosome has teeth for attachment to animals. NO eyes, anus has groove above.

Question 48

what is Ixodes ricinus a vector of?

Answer 48

- Lyme disease (caused by Borrelia burgdorferi) - tick borne-encephalitis. causes ring shape bruise/ redness on skin

Question 49

what is Dermacentor marginatus known as host habitat

Answer 49

ornate sheep tick Most mammals: sheep, cattle, deer, dogs, humans, hares, hedgehogs. lowland areas+ forest

Question 50

Dermacentor marginatus morphology

Answer 50

female: 4.6- 5.4mm after blood=15mm male: 4.8-5.8mm Silver white markings on dorsal shield has flat eyes located on edge of shield probiscus= short + thick

Question 51

Dermacentor marginatus transmitted diseases

Answer 51

Transmitted diseases : spring-summer encephalitis, Q fever, tularemia, etc.

Question 52

what is Hyalomma plumbeum known as

Answer 52

“bont-legged ticks”

Question 53

Hyalomma plumbeum morphology

Answer 53

Large body with red colour eyes = lrg surrounded by Groove= orbits proboscis= long anal groove= located caudally of anus coloured legs

Question 54

Hyalomma plumbeum vector of

Answer 54

reservoir and vector of Crimean hemorrhagic fever.

Question 55

what is Rhipicephalus sanguineus known as?

Answer 55

brown dog tick

Question 56

Rhipicephalus sanguineus morphology

Answer 56

eyes have no orbits | anal groove located caudally of anus

Question 57

Rhipicephalus sanguineus vector of host

Answer 57

Rickettsia conorii, (causes Mediterranean spotted fever), boutonneuse fever, or tick typhus. host=dogs

Question 58

Rhipicephalus sanguineus life cycle

Answer 58

completes life cycle indoors so can live in colder climates its a 3 host tick- each active stage (L,N,A) in host and then leaves host to digest blood then molts into next stage or lays eggs