問題一覧
1
Microparasites fit the following description:
normally cause transient infections
2
Concomitant immunity:
prevents superinfection
3
Malaria eradication was unsuccessful because of:
DDT resistant mosquitoes
4
anti parasite chemotherapy describes:
chemical disruption of parasite growth
5
which of the following are typical symptoms of gastrointestinal nematode infection
anorexia malnutrition impaired growth intestinal cramps
6
primary reason parasites are difficult to control
parasites have evolved to exploit host rescources and resist host defences
7
which of the following parasites cause liver failure and is commonly known as balharzia
schistosoma
8
which type of immunity is associated with chronic infections caused by macro parasites and results in partial immunity to reinfection
concomitant immunity
9
why do macro parasites, such as helminths, often cause chronic infections rather than transient ones
physically large and do not reproduce within the host
10
what is one of the survival strategies used by parasites to evade the immune system
mimicking host antigens
11
which parasite requires both humans and mosquitoes to complete its life cycle
plasmodium
12
a characteristic of microparasites
cause transient infections and result in sterile immunity
13
the group of protozoan parasites are:
amoeba flagellate ciliated sporozoa
14
traits of the molecule responsible for antigenic variation in Trypanosoma Bruce are:
a surface glycoprotein, highly immunogenic, encoded by large gene family, regulated by gene switching
15
the principle treatments for infection with Leishmania species is/are::
drugs with toxic chemical antimony
16
large amounts of glucose is consumed by leishmania for
energy for macrophage infection
17
the correct order for Toxoplasma gondii infection of a cell is:
attachment > tight junction forms
18
which of the following is an advantage of a parasite lifestyle
unlimited food supply from host
19
what is a key challenge faced by parasites during their life cycle
avoiding detection by host immune system
20
which of the following are examples of indirect transmission of a parasite
plasmodium transmitted by anopheles mosquitoes
21
which mechanism does a parasite use to evade removal by its host
specialised claws of lice to grasp hair or feathers
22
how do some parasites synchronise their life cycle with host behaviours
nematodirus battus hatching in spring when lambs are grazing
23
which of the following parasites is classified as a nematode
hookworms
24
parasites can influence host behaviour in which of the following ways
altering mosquito feeding habits in malaria
25
which of the following parasites is classed as a protozoan
plasmodium
26
which of the following parasites is a flatworm
schistosomes
27
which of the following parasites is transmitted via the fecal-oral route?
entamoeba histolytica
28
which of the following are classified as a parasitic anthropod
fleas
29
which of following parasites is transmitted by a mosquito vector
plasmodium
30
which of the following belongs to a group of flagellates
trypanosoma
31
what is the suspected reservoir host for ebola virus
fruit bags
32
which of the following is a primary symptom of ebola virus infection
high fever, chills, muscle pain
33
how is the ebola virus primarily transmitted
direct contact with infected bodily fluids
34
which of the following is a key method to control the spread of ebola during outbreaks
training health workers in contaminated procedures
35
what is the primary transmission stage or giardia
cysts
36
which organelle in giardia is involved in iron-sulfur cluster biosynthesis
mitosome
37
which of the following is a characteristic of (+)ssRNA viruses?
their lifecycle include uncoating, replication and release
38
what is the primary function of trophozoites in giardia
absorbing nutrients across their membrane in the gut
39
what type of organism is a schistosome?
helminth
40
what compartment of the body does schistosomes occupy
bladder, rectum, portal veinous system
41
are schistosomes single or multicellular during vertebrate host life cycle stages
multicellular
42
what type of organism is lymphatic filariasis
helminth
43
which compartment of the body does filariasis occupy
lymphatic system
44
is filariasis single or multilcellular
multicellular
45
what type of organism is trypanosoma brucei
protozoan
46
what compartment of the body does trypanosoma brucei occupy
lymphatics, blood stream
47
is trypanosoma brucei single or multicellular in vertebrate host life cycle stages
single-celled
48
what type of organism is Ascaris
helminth
49
what compartment of the body does Ascaris occupy
GI tract
50
is ascaris single or multicellular
multicellular
51
what type of organism is leishmania
protozoan
52
what compartment of the body does leishmania occupy?
skin
53
is leishmania single or multicellular
single celled
54
which of the following is a characteristic of trypanosoma cruzi
they have a kinetoplast, which contains mitochondrial DNA
55
how is trypanosoma cruzi transmitted to humans
by scratching skin where triatomine bug feces are deposited
56
which stage of trypanosoma cruzi responsible for systemic spread in human body
trypomastigotes
57
why is detecting trypanosoma cruzi infection difficult during early stages
antibodies take years to appear in bloodstream
58
which of the following parasites is transmitted by sandflies
leishmania
59
what is major limitation of antimonial drugs when treating leishmania
toxic with side effects
60
which organelles are characteristic of apicomplexa (malaria) and essential for host invasion
rhoptries and micronemes
61
which of the following is caused by toxoplasma gondii
toxoplasmosis
62
what is the initial stage of plasmodium injected into humans during a mosquito bite
sporozoites
63
which stage of plasmodium is responsible for relapses in malaria
hypnozoites
64
what is primary pathology cause by plasmodium during erythrocytic stage in malaria
anaemia due to red blood cell destruction
65
which genetic trait in humans provides resistance to severe malaria
sick cell trait
66
what happens during the sporozoite stage of the plasmodium life cycle in malaria
sporozoites are injected into the human host by anopheles mosquitoes and travel to the liver
67
during the liver (exoerythrocytic) stage what happens to sporozoites
they multiply asexually via schizogony to produce merozoites
68
what distinguishes the hypnozoite stage in the lifecycle of plasmodium in malaria
it allows the parasite to remain dormant in the liver and cause relapses later
69
what happens during the blood stage of plasmodium in malaria
merozoites invade red blood cells, replicate and release daughter cells
70
how do sporozoites produced in the mosquito kidgut complete the lifecycle
they migrate to the mosquitos salivary glands, ready to infect a new host
71
what happens during the schizogony stage during the plasmodium lifecycle in malaria
asexual reproduction in the liver and red blood cells to produce many merozoites
72
what occurs during exflagellation in plasmodium cycle in malaria
male gametes are released following three rapid nuclear divisions
73
how do sporozoites become infective to humans
by migrating to the mosquitoes salivary glands after leaving the haemocel
74
how does sick cell anaemia provide resistance to P.falciparum malaria
by making red blood cells less fragile and less hospitable to the parasite
75
what is the role of CSP protein in the sporozoite stage of plasmodium in malaria
acting as a primary antigen targeted by RTS,S vaccine
76
what is the mechanism of action for artemisinin derivatives in treating malaria
reacting with iron in the parasite to generate toxic free radicals
77
what genetic factor prevents P.vivax infections in some populations
the absence of the duffy antigen on red blood cells
78
which of the following is the definitive host for toxoplasma
cats
79
what is the most common source of toxoplasma gondii infection in humans
consumption of contaminated meat
80
how is the sexual cycle of toxoplasma gondii linked to its definitive host
it takes place in the intestinal cells of felids, producing oocysts excreted in faeces
81
what role do microneme proteins play during toxoplasma gondii invasion
they facilitate adhesion to the host cell surface
82
what is the primary phenotypic characteristic of tachyzoites
they divide rapidly, forming rosettes and causing acute infections
83
what is the main phenotypic difference between tachyzoites and bradyzoites
bradyzoites divide slowly and are not associated with mitochondria, while tachyzoites divide rapidly and associate with mitochondria
84
which group is at highest risk of developing fatal toxoplasmosis
individuals with suppressed T-cell counts (eg.AIDS patients)
85
which brain region shows increased activity during toxoplasma gondii infection in rodents
amygdala
86
what is the causative agent of toxoplasmosis
toxoplasma gondii
87
what percentage of global population is estimated to carry toxoplasma gondii
20%
88
in healthy human, which phase of toxoplasma gondii infection is most common
chronic phase with asymptomatic tissue cysts
89
which of the following statements is true about nematodes
nematodes have simple morphology and are highly adaptable
90
what is the infective stage of most gartrointestinal nematodes
eggs
91
what is the defining characteristic of trichuris truchiura (shipworm) infection
chronic inflammatory response and rectal prolapse
92
what is primary pathology in lymphatic filariasis
blockage of lymphatic vessels, leading to lymphoedema and fluid imbalance
93
which species of schistosoma is primarily associated with urinary tracy pathology
schistosoma haematobium
94
what is the primary source of pathology in chronic schistosomiasis
immune responses to eggs trapped in tissues such as the liver or bladder
95
how are DALYs (disability adjusted years) used to quantify the impact of helminth diseases
by summing years of life lost (YLL) and years lived with disability (YLD) weighted for severity
96
why is intensity a more informative measure than prevalence in helminth infections
itbaccounts for the number of worms per host, which influences pathology and transmission
97
which environmental factors are most critical for the transmission of hookworm infections
rainfall and temperature
98
why did chemotherapy alone fail to eradicate hookworm in the southern usa
rapid reinfection due to poor sanitation
99
what are the 3 components of the WASH strategy for helminth control
water, sanitation, hygeine
100
why is sanitation important in controlling Ascaris
reduced exposure to infective eggs in the environment