Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Pathology > Parasitology > Flashcards

Parasitology Flashcards

1
Q

What is the definition of parasitism?

A

Organisms that use another organism, with deleterious but not lethal effects on the host

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What is the difference between symbiosis and commensalism?

A

Symbiosis - positive for both

Commensalism - no negatives for the host

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Describe convergent evolution in parasites

A

Parasites with different origins facing same selection pressures and challenges evolve to be similar

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What 3 things does the host provide?

A
  1. Energy and nutrients
  2. Shelter
  3. Mobility and dissemination
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What is immunomodulation?

A

Calibrating immune respones to make host more efficient

Hookworm -> reduces likelihood of autoimmune disease

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

How do parasites cause direct behaviour modification of hosts?

A

Switching genes on and off to favour their transmission

Eg Toxiplasma living in brain of rats to get inside cats

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What does landscape of disgust cause?

A

Aniamls to move on from an infected area even if there is food there

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What does coevolution cause?

A

Results in balance between host and parasite causing lower-cost immune response and decreased pathogenicity

“learn to live with each other”

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What are 2 key attributes that decrease during coevolution?

A

Host immune response

Parasite virulence

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Who has more opporutinty for genetic change?

A

Parasite - E.coli has new generation every 20 minutes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What is the red queen hypothesis?

A

A species must adapt not only for reproductive advantage, but because other organisms are also evolving

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What are 2 ways hosts can get around the fast parasitic generation times?

A
  1. Sex -> multiple copies of genes so if parasite becomes resistant to phenotypic gene our next generation has a backup (parasite resistant phenotype)
  2. Adaptive immunity -> evolve in real time to new pathogens
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What are two options for the host when dealing with parasites?

A

Resistance - coevolution between host and parasite

Tolerance - no immune response brought on

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What is host switching?

A

Ability of a parasite to survive in a new host species

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What is host adding?

A

Addition of extra hosts that expands distribution and aids transmission
Each additional host needs new set of parasite adaptations

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What is a protist?

A

eukaryoite, single cell organism

Nuclei, organelles, mitochondria and can have flagella

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What 2 lineages show a predisposition for evolving into parasites?

A

Apicomplexans and kinetoplastids

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What are the 3 major groups of protists?

A

Metamonda
Apicomplexan
Kinetoplastida

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What are the 3 types of Metamonada?

A

Diplomonads
Trichomonads
Histomonas

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What are 2 types of diplomonads and what do they do?

A

Giardia - anaerobic, flagella, faecal oral transmission, prevents nutrient and water absorption in small intestine causing diorrhoea

Spironucleus + hexamita -> found in intestine of vertebrates - recognised disease of king parrots

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What are 3 types of tritrichomonads?

A

Trichomonas gallinae

Tritrichomonas and tetratrichomonas

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

What is tritrichomonas gallinae? (where does it live, who does it infect, how does it transmit)

A

Metamonada
Pigeons and doves
Lives in upper GIT or repro tract
Oral-oral transmission (feeding young)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

What do tritrichomonas and tetratrichomonas do?

A

Tritrichomonas foetus is veneral of bovine and causes diarrhoea in cats

Tetratrichomonas -> found in vertebrates as GIT parasites

24
Q

What does histomonas Meleagridis do?

A

Intestinal parasites of poultry
Cause histomoniasis - invasion of caecal wall and liver

Larvae come out and eaten by earthworms, then poultry again

25
Q

What defines a kinetoplastida?

A

Has insect vectors

Heteroxenous -> need multiple host species for lifecycle, veterbrates are intermediate hosts (sexual reproduction here)

26
Q

What are two types of kinetoplastida?

A

Leishmania

Trypanosoma -> indirect life cycles with insect vectors

27
Q

What are two groups of trypanosoma?

A

Salivarian - transmitted in saliva of insect

Stercorarian -> transmitted in faeces of haematophagous insect, excreted onto skin of host. penetrate wound and re-enter insect through blood meal

28
Q

What defines an apicomplexan?

A

Complex life cycles with multiple stages involving animal hosts, vectors and intracellular life stages

Schizonts

29
Q

What are 3 types of apicomplexans?

A

Piroplasms
Malarial parasites
Coccidians

30
Q

What do piroplasms do? (definitive hosts, intermediate stage location, reproduction site)

A

Tick parasites are definitive host - sexual reproduction here

Intermediate stages in vertebrates (cattle) causing tick fever

Reproduce in blood/endothelium by clonal reproduction (schizonts)

31
Q

What are vectors, definitive hosts and where does reproduction occur in Malarial parasites?

A

Vectors -> biting dipteran insects

Definitive host -> dipteran insects (sporogony here - asexual spore production)

Merogony in hepatocytes and blood/endothelial/macrophages

32
Q

Coccidians - host, what do they cause, examples of species

A

Hepatozoon -> infect invertebrates and can infect vertebrates as intermediate hosts

One host species, blood diarrhoea

Neospora, toxoplamsa -> infects vertebrates without insect life stages

33
Q

Toxoplasma, neospora life cycle type

A

Monoxenous or limited host range with no intermediate host

34
Q

Reproduction of coccidians

A
  1. Oocytes shed in faeces
  2. Sporulate
  3. After ingestion, release sporozoites that invade intestinal epithelial cells
  4. Reproduce by binar y fission
  5. Cell ruptures + releases merozoites which infect other cells
35
Q

Which host is sexual reprocution completed in?

A

definitive host

36
Q

What is an adverant host?

A

Dead end host

37
Q

What is a paratenic host?

A

Ends up in host, not ideal, but can develop in it

38
Q

What is a metazoan?

A

Multicellular eukaroyte

39
Q

What are the 3 groups of metazoans?

A

Nematodes - roundworms
Platyhelminths - flatworms
Arthropods

40
Q

How many animals are nematodes?

A

80%

41
Q

How are nematodes described?

A

Free-living
Microscopic to over 1m
Have GIT and anus
Feed on host or GIT nutrients

42
Q

What are the nematode life stages?

A

Dioecious adults
Lay eggs or are ovoviviparous
Larvae hatch from eggs and moult through stages (L1, L2, L3)
Have to get to L3 to infect

43
Q

What hosts do nematodes have?

A

Some have multiple intermediate hosts

44
Q

Where do filarial nematodes live? Do they have vectors or intermediate hosts?

A

Pleural + peritoneal space, heart, joints

Produce larvae (microfilaria)

Intermediate hosts ingest these and transmit by biting another defintiive host

Insect vectors

45
Q

What are 3 groups of platyhelminths?

A

Cestodes (tapeworms)
Trematodes (flukes)
Monogeneans

46
Q

what is the structure of platyhelminths?

A

No body cavity, no GIT
No ciruclartory or respiratory organs

Flat -> allow nutrients to diffuse through

Dont feed on host, only GIT nutrients

47
Q

Where is liver fluke found?

A

Cattle and sheep

Only grow where grass is wet (embryonate in water)

48
Q

What are 2 types of arthropods?

A

Insects (flies, mosquito, lice)

Arachnids - ticks and mites

49
Q

How are arthropods described and what do they cause?

A

Important vectors for other parasites

Associated with production losses, hypersensitivities (flee allergy dermatitis)

Tick paralysis, queensland itch, flystrike

50
Q

What things can change to cause an emerging infectious disease?

A 
New host demographic
Changed distribution in space and time 
Changes in virulence
Cycle of behaviour 
Increase in incidence, fatality
51
Q

What are 6 emerging infectious diseases?

A 
FMD
Lumpy skin disease
JEV
Hendra
African swine fever
Highly pathogenic avian influenza
52
Q

What is spillover?

A

Infectious disease reaches new species

Rarely leads to host switch

53
Q

What are 7 steps of spillover?

A
  1. Need reservoir species in place and time where spillover occurs
    2, Need infectious agent present
  2. Host needs to be shedding
  3. Environmental contamination
  4. Survival outside host
  5. New host exposure
  6. Infectability of new host (right receptor for spike protein? can innate immunity stop it?)
54
Q

What is spillback?

A

Spilt over to new host then back into reservoir again with new attributes

55
Q

What is a reservoir?

A

Co-evolves with

56
Q

What is R0?

A

Average number of individuals a person will infect
Cant survive long term if this is 1 or less than
Higher the value -> more infectious

Pathology (6 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions