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75 Cards in this Set
- Front
- Back
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Charateristics of Nematodes |
-unsegmented -body cavity a pseudocoel -complete gut w/ anus -sexes usually seperate -have cell #s constant across individuals of a species |
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Female Ascaris -bulbous pharynx -gonads -multiple ovaries, oviducts -uterus is double-branched -ovaries at the end of oviduct -larger in size than males |
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Male Ascaris -have curved posterior end -have spicule that helps male attach to female -copulatory bursa -mouth
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Ascaris lumbricoides -large intestinal roundworm -have 3 prominent lips -only infective in j3 stage -infected by ingesting contaminated food, water, or human feces or soil with eggs in it
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Ascaris lumbricoides Life Cycle |
-unembryonated eggs are ingested -hatch in duodenum then enter the lymphatics -migrate through the body and accumulate in almost every organ -move up the respiratory tract to the pharynx and are then swallowed. (J4 stage) -pass through the stomach to the small intestine and become adults |
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Ascaris Eggs |
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Charateristics of Trichostrongyles |
-mostly parasitic -small, slender worms
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Haemonchus contortus |
-Sheep Stomach Wire Worm (Barber Pole Worm) -no intermediate host |
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H. contortus Life Cycle |
-unembryonated eggs ingested by sheep while grazing -develops into embryonic stage in stomach -J1 hatches and continues to develop to J3 which is infective
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Toxacara canis -simlar to Ascaris -found in dogs -viseral & ocular larval migrans -pre-natal infection can ocurr |
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T. canis Life Cycle |
-eggs are passed in feces -eggs develop to stage with embryonic larva in external enviroment -eggs are injested by dogs or humans -humans are paratenic hosts (not intentional) so development will stop there -dogs are definitive host -larvae will migrate to various organs and can be throughout the body |
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Geohelmiths |
Worms that have a part of their life cycle associated with soil -Ascaris -Hookworms -Whipworms -Stongyloides |
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Toxacara cati |
-found in cats -have cervical alae |
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Baylisascaris procyonis |
-common parasite of racoons in North America -juveniles migrate throughout body and can even get into the nervous system (neural larval migrans) -occurs almost exclusively in children less than 2 years old -transmitted through racoon feces (communal poop grounds) |
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B. procyonis Life Cycle |
-a paratenic host (small mammals & birds) with encysted larvae is eaten by a raccoon -larvae develop into adults in small intestine -eggs are passed in feces and become embryonated in the external enviroment -paratenic host or raccoon ingests eggs again via feces |
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Hookworm Characteristics |
-eat blood -live in the small intestine of host -anterior end is curved dorsally (hooked) -bucal capsule helps ID species -esophagus are bulbous, not just straight -use enviromental cues to know when host is coming -a lot of development happen in soil -can be picked up through contact with soil or from feces (poor latrine settings/ sanitary conditions) |
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Hookworm Life Cycle |
-eggs are passed in feces -eggs develop into J3 injective stage in soil (must be moist!) -juveniles penetrate the skin on humans or can be ingested orally -migrate through circulatory sytem to lungs -juveniles molt in lungs then travel to small intestines via the trachea -adult worms develop in the small intestine, mate, and reproduce |
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Hookworm copulatory bursa |
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Necator americanus -note the two broad cutting plates -most common parasite in most of the world (85% of infections) |
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Anglostoma caninum -most common hookworm in dogs -cuteaneous larval migrans in humans -dog is definive host, not humans (intermediate) -has 3 seperate teeth on either side of mouth -have 2 ventral plates -males have a copulatory bursa |
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Pinworm Characteristics |
-very common and contagious, wide variety of hosts -drift on fabrics (bedding, clothing, curtains, etc.) -infectious in large groups of people (hospitals, etc.) -does not cause serious pathology (its just embarrassing!) -only a few mm long -tail end has a sharp tip -females are larger than male worms -males have cervial alae |
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Pinworm Life Cycle |
-eggs are ingested by humans -larvae hatch in the small intestine -develop between the small and large intestine (ileocercal) -very quick development (4-6 hours) -are adults at the end of the large intestine
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Enterobius vermicularis -Ichy Butt Disease -some females will travel back up the anus after laying eggs (retroinfection) |
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E. vermicularis Male is smaller than the female, considerably |
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Male pinworm cervical alae *look closely at posterior end |
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Whipworm Characteristics |
-are thick with a thin anterior end -males have coiled tails and are smaller and have spicuales -long, thin anterior burrows into intestinal wall -feed on blood -both sexes have a single gonad -eggs require moist and shady soil |
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Trichuris Life Cycle |
-infected by improperly washed veggies (soil), and poor sanitary conditions -eggs are released from the body and into to soil via feces -most of development happens in the soil -development continues once ingested by human. -encysts in lieberkuhn of large intestine and develops into an adult -adults can live up to four years in humans |
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Trichinella Life Cycle |
-acts similarily to a virus -ingested by humans by consuming undercooked meat, whether that be pork or a large carnivore -Sylvatic and domestic life cycles -hatch in small intestine and penetrate intestine through the mucosa to get into muscle tissue -Take over muscle fiber, develop nurse cell that changes body's cells around it and makes them get the nurse cell nutrients
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Trichinella spiralis encysted a muscle tissue |
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Trichinella Juv in Nurse Cell |
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Dracunculus medinensis |
Guinea Worm -transmitted from unsanitary water, ingesting copepods that live in water
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Guinea Worm Eradication Efforts |
1. Supply safe drinking water; tube wells and hand pumps = people not entering water 2. Health education: cloth filters for households and pipes for field workers 3. Early case containment: treatment and bandaging of lesions = no water contact 4. vector control: chemical Temphos to kill copepod (intermediate host) |
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Guinea Worm Life Cycle |
-Person has an adult female worm -when female and male worms mate (in the small intestine) and give birth (live young) they release a chemical that causes that blister on the body -people seek relief by going into cool water, but that signals the blister to burst. -The female exits the body a little bit and the juvs are expelled from the body of the female (uterus) -female remains in the body -Juvs must be consumed by a copepod withing 3 days of being released -once ingested they continue development and wait to be ingested by their definitve host (human) via bad drinking water |
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Filarial Worm Characteristics |
-microfilariea = larval stage -intermediate host/vector = mosquito -no reservoir host -causes elepantasis, lymphatic filariasis
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Wuchereria brancrofti -causes elephatiasis
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Wuchereria brancrofti Life Cycle |
-mosquito bites infected human and takes up microfilariae in blood meal -develop into juv in gut of mosquito -mosquito bites another human and injects juvs into new host -juvs migrate into the lymphatics to lymph nodes -juvs develop into adults in lymphatic vessels -adults reproduce and microfilariae migrate to bloodstream |
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Onchocerca volvulus from nodule (adults) -causes River Blindness -intermediate host = black fly -black fly life cycle requires fast moving water -causes the skin to be very itchy -knotted together in pairs and groups in subcutaneous tissue (nodules) |
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Onchocerca volvulus Life Cycle |
-similar to that of W. brancrofti -fly bites a human and takes up microfilarae and then bite another human -it takes about 1 year for the microfilarae to develop -adults form nodules (onchoceracoma) nder the skin in various parts of the body -microfilarae are still in the blood stream waiting to be taken up by a fly |
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Sclerosing keratitis (from O. volvulus) |
-hardening of inflammation of the cornea -result of the body's immune response to dead microfilarae -causes loss of vision and damage to the retina and choroid
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Loa loa -intermediate host = deer flies -also known as the eyeworm -appear tranparent -can be seen under the skin as well |
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Loa loa Life Cycle |
-deer fly bites a person and takes up microfilarae in blood meal -females birth live young -adults can live about 15 years in person -adults are found in subcutaneous tissue |
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Dirofilaria immitis -Dog Heartworm -vector (intermediate host) is the mosquito -adults take about 5 months to mature -inhabit the right side of the heart -prevent with Ivermectin -very rare in humans but would be in the lungs |
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Phylum Nematomorpha Characteristics |
-parasites of arthopods, primarily beetls and crickets -occur in high density, tangled masses (mating event) -adults are not found very often, juvs much more common -range from pure white to black in color (have lighter color at anterior end) -body cavity of adults is filled with gonads |
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Protelean Parasitoids |
-aka mermithids -insects in which only the immature stages are parasitic |
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Sphaeularia bombi Life Cycle |
-parasite of bumblebees (only the queens) -modifies behavior -adult queen bee is infected while she hibernates -worm begins to grow in spring when bee emerges -the worm turns its uterus inside out and it projects off of the body -worm inhibits the release of a hormone that stimulate nest building and bee will only feed herself (no other bees) -eggs are released in feces in her burrows and wait to be ingested by another queen |
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Phylum Acanthocephala Characteristics |
-have a hooked proboscis, and neck region (varies by species) -about 1000 species in phylum -all do some sort of behavioral modification -no digestive system -separate sexes -absorb nutrients through body wall -proboscis is retractable -females = free floating uterine bells -males = 2 testes, cement duct -definitive host= birds, mammals, fish -intermediate host= arthropod
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Proboscis (varies greatly by species) -used to attach to host
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Moniliformis dubius Life Cycle |
-Definitive host= rat -intermediate host= cockroach -eggs hatch fully embryonated and are infective right away -larval infective stage= acanthor -larval stage= acanthella (in body cavity) -creates a cyst (cystacanth) -juvs escape from cyst and make their way to intestine |
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For Reference |
M. dubius Life Cycle |
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Progression of a Acanthocephala |
Acanthor -> Acanthella -> Cystacanth -> Adult |
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Homosexual Rape and Sexual Seduction in Moniliformis |
-males will cement off the females tubes once he has deposited his sperm -males will also cement other males in an effort to take our the competition |
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Egg with an acanthor inside |
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Behavorial Modifications of Ancanthocephalas |
Example: Polymorphus paradoxus -mallards and amphipods (at the bottomof the lake) -infection changes amphipod behavior so that they will to up to the surface more and that puts them at a greater risk of predation (from ducks) |
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Phylum Mollusca Class Bivalvia Family Unionidae (Freshwater Bivalves) Glochidium Larval Stage |
-larva attach to fins, skin, or gills of fish -they fall of of the fish as it moves (distributed this way) 3 Different Infection Method: -Free floating -mantle (attractive lure) -conglutinates (ovisac) that looks like a prey item -not always attached to bivalve, but also close by -larva are spread by a fish attacking the lure and breaking open the ovisac |
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Phylum Pentastomida Characteristics |
Tongue worms -found in the nasal tract of reptiles (definitive host, primarily) -have 2 pairs of hooks in mouth region -have seperate sexes -singular tubular testes in males -single ovary in females -females only mate once
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Pentastome Nymph -infective in definitve host |
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Pentastome Life Cycle |
-eggs are ingested by intermediate host and travel to intestines -make their way through the intestinal wall and into the body cavity -reproduction occurs in the respiratory tract |
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Phylum Annelida Class Hirundiae
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Leeches! -not all spps are parasitic -have two suckers -most live in fresh water -form a slit in the skin to take blood meal from and continually take blood
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Phylum Arthropoda Characteristics |
-segmented, but segments fused into funcional units (tagmata) -joined appendages -rigid exoskeleton -complex muscles for moving exoskeleton -complete gut -open circulatory system -various respiration structures -fully developed extrectory systems -seperate sexes, internal fert -Diapause (developmental arrest)
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Subphylum Crustacea Subclass Copepoda |
-parasites of fishes and other aquatic animals |
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Subphylum Crustacea Subclass Branchiura |
Fish louse -ectoparasites of fish
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Subphylum Crustacea Subclass Cirripedia Order Thorasica |
barnacles; order thorasica = typical barnacles -larval stage= nauplius -through a series of molts = cypris -when attached to substrate = adult -filter feeders |
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Subphylum Crustacea Subclass Cirripedia Order Rhizocephala |
Root Heads -all are parasitic castrators
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Sacculina carcini |
-parasite of European Green Crabs -larval stage is a typical barnacle (but looks nothing like one) -adults lack a digestive system, but get nutrients from a root network established throughout the body
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Sacculina carcini Life Cycle |
-adult crab (male or female) is parasitized, has a fertilized externa -externa releases nauplius larva -male and female larva molt several times to become cypris -Kentrogen (cypris female) seeks out a host and attaches to the soft spot on crab (gills, under shell/tail) -She uses a syringe apparatus to inject a vermigon (worm) into host -vermigon sits on the nerve cord and begins to grow into a "root network" -this presses on the nerve cord which stops secretions that make the shell stay hard -the soft shell allows the externa to penetrate the shell -the male cyrpis seeks out a virgin female externa and transforms into a trichogon (glob of reproductive organs) and cements the tube off -once fertilized the externa grows significantly -develop of external destroys ovaries in female crabs and takes away gland that makes males, males -crabs care for externa like its their own brood sac (females and males!) |
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Parasitic Castration as a Trophic Strategy |
1.) Differs from typical parasites in that castrator pathology is not intensity dependent 2.) Reduces host reproductive output 3.)Parasitized host are not removed from pop'n 4.) Resource availability does not increase **Like the walking dead! |
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Kentrogen -female cypris |
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Vermigon -worm injected by female cypris |
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Subphylum Crustacea Class Malacostraca Order Amphipoda |
Whale lice
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Hyperiidean Amphipods -Salp is the host -eat out the insides of host and ride along in shell of body (parasitoids) -Kill host |
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Subphylum Crustacea Class Malocostraca Order Isopoda Family Ganthiidae |
Parasitic Larvae on Fishes ("Ticks of the Sea") -adults are free-living -look like pill bugs -are all protelean (larval stage is parasitic but adult stage is free living) -attach to fish, take blood meal, and detach
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Order Isopoda Family Cymothoidae |
Parasites of Fishes -found in both marine and freshwater habitats -all take a blood meal -all are parasitic -attach to gills, fins, tongue -females are much larger than males -all start out as protandrous (all born male) hermaphradites -can serve as the tongue |
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Order Isopoda Family Bopyridae |
Parasites of Decapod Crustaceans -shrimps, crabs, lobster -female attaches to host and male attaches to female -take blood meals (a lot of blood!) -parasitic castrator
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Bopyrid Life Cycle |
-the shrimp has a female and male attached to the female -they reproduce and female releases epicaridium (larva) -epicaridium attach to copopod then become micronisucus (larvae) -development continues into a cryptoniscus then an adult |
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Order Isopoda Family Entoniscidae |
Parasites of Crustaceans -internal -crabs, shrimps -life cycle is the same as the bopyrid's -enter crab through gill chamber -grow and take over testes/ovaries (castration) -females reproduce -host creates a sheath around parasite and creates and opening for parasite to release eggs |
