Quiz 1 Pages 1 - 4 Flashcards
Describe the exoerythrocytic cycle. Where does it occur? What parasite possess it as a part of their reproduction.
Parasites (Sporozoites) infect liver cells, form schizonts (multiply by schizogony), and rupture (release merozoites). Can reinfect more liver cells and therefore continue the cycle. In the liver. Plasmodium.
What is the natural substance used to kill Plasmodium falciparumi?
Quinine
What are the two terms for Parasite ecological niches and define them?
Coelozoic (live in hollow organs) and histozoic (live in tissues)
What are the three major families of Kinetoplasta?
Bodonidae, cryptobiidae, trypanosomatidae
What is the lifecycle of Trypanosomtidae called and define?
Heteroxenous - requires more than one host
What are the two parasite groups based on their development inside ahost insect?
Salivaria and Stercoraria (describe them)
What are the three Salivaria Trypanosoma brucei subspecies?
T b brucei, T b gambiense, T b rhodisense
Which parasite causes slow developing African trypanosomiasis?
T b gambiense
What is the infective stage of African sleeping sickness?
Metacyclic trypomastigotes
What is the full name of the parasite that can be found in cats that are known to influence the behavior of miceby making them bold and attracted to cat pee?
Toxoplasma gondii
Name two species of Plasmodium that cause malaria.
P falciparum, P ovale, P malariae, P vivax
What word can be used to describe a parasite shared between animals and humans?
Zoonotic
In the context of Parasitology, define “commensalism”
Parasite benefits, host is neither helped nor harmed
What is an important component of bug spray, designed to repel mosquitos?
DEET.
African Trypanosomiasis (Sleeping sickness) is transmitted to humans by tsetse flies. What is the genus name of the tsetse fly?
Glossina
There are several possible ways of treating African Sleeping Sickness. Name two of the medications that can be used to treat it.
Pentamidine, Suramin, Sanofi
Where in humans does the Trichomonas vaginalis parasitize? Name two ways in which it can be transmitted.
Vagina, urethra, and prostate. Sexual disease or through damp clothes.
Name the threegenera within sarcodina which are known to contain parasites or commensals of humans
Entamoeba, endolimax and iodamoeba
How is Entamoeba histolytica transmitted? in what form is it transmitted?
Ingestion of cysts on fecally contaminated food or hands.
Cysts.
List 3 ways to control/prevent malaria
Medication, bed nets, screens, education, treat building walls, special clothing, etc
What are the 3 cylces involved in Plasmodium falciparum’s life cycle?
Exo-erythrocytic, erythrocytic and sporogonic
What is the name of the accidental parasite that was mentioned in class?
Naegleria fowleri
What is the difference between a parasite and a parasitoid?
Parasite = smaller than host, want host to live long enough for them to get what they need Parasitoid = similar size to host, doesnt care if host dies
Are protozoa ammonotelic or uricotelic?
Ammonotelic
Define Heteroxenous
Requiring more than one host to complete their life cycle
What is the name Apicomplexa derived from, and what are its specialcomponents?
Apical complex (present in all members of the group) –> polar ring, roptry, micronemes, and conoid
Give a brief description of what occurs during sporogeny, merogeny, and gametogeny.
Sporogony = formation and maturation of infective stage Merogony/Schizogony = asexual reproduction (results in multiple daughter cells) Gametogony = formation of gametes (sexual phase)
Where does the exo-erythrocytic cycle occur?
The liver
Define definitive host and intermediate host
Definitive host = where the parasite reaches sexual maturity
Intermediate host = where development occurs (only asexual reproduction)
Name 3 organisms Metronidazole can be used to treat
Entamoeba histolytica, trichomonas vaginalis, and giardia lamblia.
What parasites are phagocytized by phagocytes in humans?
Leishmania (3 species)
What is a common reservoir of Leishmania?
Dogs and rodents are common reservoir of Leishmania
List three organelles parasites use for locomotion.
Flagella, cilia, pseudopodia
Which parasite causes sleeping sickness to develop slowly?
T b gambiense
Which parasite causes sleeping sickness to develop rapidly?
T b rhodiensie
Which parasite causes chagas disease?
T cruzi
Which species of Leishmania are pathogenic for man?
L donovani, L tropica, L brasiliense
What is a facultative parasite?
Can live without a host (or with one)
What is a paratenic host?
Transport host. No development occurs but remains alive and infectious to another host.
What are the factors that affect a parasites ecological niche?
The resources provided by the host and abiotic conditions.
Define: Metapopulation, intensity and prevalence?
Metapopulation = all the infrapopulations within a single host species in the ecosystem Intensity = average number of parasites per host Prevalence = % of hosts infected at a given time
List 5 morphological features of protozoa
Plasma membrane, pellicle, alveoli, glycocalyx, pellicular microtubules, undulating membranes, Golgi apparatus, microbodies
What is schizogony?
multiple fission – nucleus divides numerous times before cytokinesis occurs, resulting in many daughter cells at the same time
What is a kinetoplast?
Disc shaped, dense, darkly staining, DNA containing organelle within the mitochondrion
What are the 2 groups of trypnanosoma species based on their development in insect host and explain?
Salivaria and Stercoraria
What are the signs/stages of African sleeping sickness disease
1) Chancre
2) Winterbottom signs
3) Neurological symptoms (and marked wasting)
List 2 vectors of American trypananosmiasis
Triatoma, Panstongylus, Rhodnius
What is Ramana’s sign?
True bug bite on face - eyelid and area around eye gets really swollen (swelling of the periorbital area)
What are the morphological features of trichomonas vaginalis? Its habitat in host? And treatment?
1 nucleus, 4 anterior flagella and a lateral flagellum attached via undulating membrane.
Vaginal/urethral and prostatic tissue
Metronidazole
What are the signs and symptoms associated with complicated malaria
Cerebral malaria (abnormal behaviour, impairment of consciousness, seizures, coma, etc)
Severe anemia and hemoglobinuria due to hemolysis
Pulmonary adema or ARDS
Abnormalities in blood coagulation and thrombocytopenia
Cardiovascular collapse and shock
What is the treatment for Babesia microti?
Clindamycin and quinine
What is the definitive host of toxoplasma?
Cats (wild and domestic)
What parasites can Metronidazole be used to treat? Give 2.
Giardia lamblia, entamoeba histolytica, trichomonas vaginalis
What are the 4 components of the Apical complex?
Polar ring, micronemes, roptry, conoid
Why is there no one drug to cure malaria?
Chemicals are only good for a few years because plasmodium changes its surface antigens and can get resistant very quickly.
What is the difference between salivaria and stercoraria parasites?
Salivary = develop in the anterior part of the insect’s digestive tract and undergo anterior station development before travelling to salivary glands. Parasites are transmitted via saliva/bite. Stercoraria = develop in the handgun of insect’s digestive tract and undergo posterior station development and move to the anus. When arthropod feeds, it defecates, and when host scratches the bite that introduces the parasites into the bite wound.
Define ammonotelic, ureotelic and uricotelic and give an example of an organism that does each.
Ammonotelic = excrete most of their Nitrogen as ammonia. Ex: any named protist, bony fish, etc Ureotelic = excretes excess nitrogen as urea. Ex: Mammals, frogs turtles, humans, etc Uricotelic = excretes nitrogen as uric acid or its salts Ex: birds, lizards, snakes, etc
Explain how local traditions can contribute to the spread of parasites.
Using fresh water for drinking without boiling, using a single stream for laundry/washing/drinking and therefore increasing the risks of contamination, eating certain types of food without proper preparation (ex fresh fish without cooking).
Define 2 of epizootics, zoonosis, symbiosis, and phoresis.
Epizootics: massive deaths of wild animals infected with parasites. Zoonosis: transmission to humans of parasites normally found in wild and domestic animals. Symbiosis: living together. Phoresis: travelling together.
