Parasitology Flashcards
(106 cards)
1
Q
What is parasitism?
A
A symbiotic relationship in which one organism (the parasite) benefits at the expense of the host
2
Q
Where is an endoparasite found?
A
Internally
3
Q
Where is an ectoparasite found?
A
On skin and hair
4
Q
What are the two main classifications of parasites?
A
- Protozoans
- Helminths
5
Q
Are protozoa eukaryotes or prokayrotes?
A
Eukaryotes, they have nuclei
6
Q
What are protozoa?
A
Single celled simple animals
7
Q
How are protozoa classified?
A
Based on locomotion
8
Q
Protozoa exist in what two forms?
A
- Trophozoite
- Cyst
9
Q
What happens when protozoa are in trophozoite form?
A
Cell is vegetative
Feeding off the host and multiplying
10
Q
What happens when protozoa are in cyst form?
A
Dormant and resistant phase for outside the host
11
Q
What is the method of locomotion of sporozoa?
A
No method of locomotion
12
Q
What is the method of reproduction of sporozoa?
A
Simple fission followed by sexual reproduction (2 cycles)
13
Q
What is the etiologic agent for malaria?
A
Plasmodium spp.
14
Q
What is the vector of plasmodium spp. causing malaria?
A
Anopheles mosquito
15
Q
What is the most prevalent species of plasmodium in sub-Saharan Africa?
A
Plasmodium falciparum
Responsible for the majority of malaria deaths globally
16
Q
What is the second most significant species of plasmodium?
Where is it prevalent?
A
Plasmodium vivax
Prevalent in Southeast Asia and Latin America
17
Q
What is the most prevalent parasitic disease worldwide?
A
Malaria
18
Q
What is malaria?
A
Febrile illness caused by plasmodium infection of RBCs
19
Q
What are some symptoms of malaria?
A
- Fever
- Anemia and circulatory changes
- Splenomegaly
- Bone marrow suppression
- Hemoglobinuria
20
Q
What is hemoglobinuria?
A
“Black water fever”
High amounts of hemoglobin in urine
21
Q
What is the etiologic agent of toxoplasmosis?
A
Sporozoa: toxoplasma gondii
22
Q
What is the vector of toxoplasma gondii causing toxoplasmosis?
A
Feces of infected domestic cats
23
Q
How might toxoplasma affect a pregnant woman?
A
May cause miscarriage or severe neurological damage to the fetus
24
Q
How might toxoplasma affect someone with AIDS?
A
Important cause of AIDS-related dementia
25
Toxoplasmosis requires no treatment unless symptoms are severe, except for...
* pregnant women
* HIV positive individuals
26
How is sporozoa cyptosporidium transmitted?
Fecal-oral transmission usually via water
27
What is the most common symptom of cryptosporidiosis?
Watery diarrhea
28
Rhizopods are amoeboid
What does this mean?
They can change shape
29
What are the most primitive of all protozoans?
Rhizopods
30
How do rhizopods reproduce?
Binary fission
31
What is the method of locomotion of rhizopods?
Pseudopods (false foot)
32
How do rhizopods adapt to environmental stress?
Can exist as cyst
33
What is the etiologic agent of amebiasis?
Rhizopod: entamoeba histolytica
34
Rhizopod entamoeba histolytica colonizes...
the colon
35
Which parasite causes the disease "Montezuma's Revenge" and "New Delhi Belly"?
Rhizopod: entamoeba histolytica
36
What are symptoms of acute amebiasis?
Diarrhea (occ. bloody), flatulence, cramping, and abdominal pain
37
What are symptoms of chronic amebiasis?
Alternating bouts of diarrhea and constipation
38
What class of parasite is the largest to infect humans?
Mastigophora
39
How do mastigophora reproduce?
Binary fission
40
What is the method of locomotion of mastigophora?
Flagella
41
Mestigophora exist solely in which form?
Trophozoite (vegetative)
42
What is the vector of mastigophora: trichomonas vaginalis?
Sexually transmitted
43
Is mastigophora: trichomonas vaginalis invasive?
No, non-invasive
44
Is mastigophora: trichomonas vaginalis toxin producing?
No
45
What are some symptoms of mastigophora: trichomonas vaginalis in females and males?
Petechial hemorrhaging
Persistent vaginitis in females
Chronic long term infection in males: prostatitis and urethritis
46
Mastigophora: trichomonas vaginalis exits only in ___ form
trophozoite
47
What is the etiologic agent of trypanosomiasis?
Trypanosoma spp (mastigophora)
48
What is the vector of trypanosoma spp?
Tsetse fly
49
"Sleeping sickness" is the common name for what disease?
Trypanosoma spp (mastigophora)
50
African sleeping sickness is confined to...
central Africa
51
How does African sleeping sickness progress from the tsetse fly bite?
Localized inflammation at the bite is followed by hematogenous and lymphatic spread
Colonizes small blood vessels of the heart and brain
52
What are the symptoms of African sleeping sickness?
Fever, headache, impaired mental status leading to coma and death
53
African sleeping sickness agent, trypanosoma spp, exists only in the ___ form
trophozoite
54
What is the etiologic agent of giardiasis?
Giardia lamblia (mastigophora)
55
What is the vector of giardia?
Fecal-oral
56
Giardiasis is also known as...
Beaver fever
57
What are symptoms of giardiasis?
* Diarrhea (steatorrhea)
* Cramping
* Flatulence
* Anorexia
58
What form does giardia exist in?
Both cyst and trophozoite
59
What is the etiologic agent of an oriental sore?
Leishmania spp (leads to leishmaniasis)
60
What is the vector of leishmania spp?
Sand flea
61
After a bite from a sand flea carrying leishmania spp, when will oriental sore appear?
Weeks to months after bite
62
What are the symptoms and progression of leishmaniasis (oriental sore)?
* Itchy pustules
* Lymphadenopathy
* Spontaneous healing in 5-12 months
* Depigmented scar
* If confined to skin, no further issues once scar forms
63
Only one ciliate infects humans causing intestinal disease, what is it?
Balantidium coli
64
What is the vector of balantidium coli?
Fecal-oral involving swine feces
65
Are helminths eukaryotes of prokaryotes?
Eukaryotes
66
What are the two phyla of helminths?
* Platyhelminthes (flatworms)
* Nemahelminthes (roundworms)
67
What are the three classes of worms?
* Cestodes (tapeworms)
* Trematodes (flukes)
* Nematodes (roundworms)
68
Which of the worms is the largest?
Cestodes
69
Cestodes lack...
vascular and respiratory systems
70
Describe the sex organs of cestodes
They are hermaphrodites
71
How do cestodes absorb nutirents?
Across the cuticle
72
Adult cestodes consist of what three parts?
* Scolex
* Regenerative neck regions
* Long segmented body
73
What is the function of the scolex in a cestode?
Used for attachment
74
What is the regenerative neck region of a cestode?
Immature segmented portion of a tapeworm: proglottid
75
What is the sexually maturing section of a tapeworm?
Mature proglottids
76
What portion of the a cestode will break away and release eggs?
Gravid proglottids
77
What type of host is needed for a tapeworm?
Need a primary and secondary host; humans usually incidental
78
Tapeworm can live in humans for...
decades
79
How large is a tapeworm?
May reach lengths of 10-25 feet
80
What are some symptoms of tapeworm?
* Gastric discomfort
* Nausea
* Diarrhea
* Weight loss
81
Describe the structure of tematodes
Bilateral symmetry
82
How large are trematodes?
Millimeters to centimeters in length
83
What are the sexual characteristics of trematodes?
Can be hermaphrodites or schistosomes (sexual)
84
Paragonimus westermani is an example of what type of worm?
Trematode; lung fluke
85
What is the vector of paragonimus westermani?
Ingestion of improperly cooked crab
86
With paragonimus westermani, eosinophilia and inflammation result in formation of...
a fibrous capsule
87
How does paragonimus westermani progress from inflammation?
* Formation of a fibrous capsule
* Swell and erode into bronchioles
* Can rupture pleura
* May travel to intestine and brain
88
What is the name of the Chinese liver fluke?
Trematode: clonorchis sinesis
89
What is the vector of clonorchi sinesis causing liver pathology?
Ingestion of improperly cooked fish
90
Where are clonorchis sinesis larvae released?
Where will they travel?
Larvae are released into duodenum and travel to the common bile duct
Can migrate to the pancreas
91
Migration of clonorchis senesis may cause...
* fever
* chills
* mild jaundice
* eosinophilia
* hepatomegaly
92
Which worm causes fibrosis, bile stones, and is associated with bile duct carcinoma?
Trematode: clonorchis senesis
93
How long can clonorchis senesis survive in a human host?
50 years
94
What is the only trematode that is cylindrical in shape and have both genders?
Schistosoma spp
95
Where does schistosoma spp occur in the body?
Occurs as a blood fluke
96
What is the vector for schistosoma spp?
Fecal-oral
97
How do schistosoma spp reproduce?
Male and female join for life to sexually reproduce
98
Which worm starts as an infection in the portal veins and travel to the ascending colon?
Schistosoma spp
99
Schistosoma lay eggs in...
the colon; rupture into the bowel or bladder
100
What are some symptoms of schistosoma spp?
Adult worms in intestinal tract causes abdominal pain and bloody diarrhea
101
How long can schistosoma live in a host?
30 years
102
What are the two types of nematodes?
* Intestinal
* Tissue
103
What is the body shape of intestinal nematodes?
Fusiform boy shape
104
Where must intestinal nematodes incudbate?
Eggs must iincubate outside host to become infective
105
How many offspring are produced by intestinal nematodes?
Thousands of offspring
106
