WorksheetsParasitology II
Total questions: 27
Worksheet time: 27mins
Arthropods that parasitize humans fall into 2 groups. These are:
diptera and lice
fleas and lice
ticks and mites
mosquitoes and flies
arachnids and insects
A key difference between arachnids and insects is:
arachnids feed on the hosts blood, insects dont
arachnids have an exposed hypostome, insects dont
insects have 2 body segments, whereas arachnids have 3
insects have antennae, arachnids have palps
Leishmania spp. are what kind of protozoan?
flagellate
apicomplexan
sporozoan
cilliate
amoebic
T or F. Mite larvae develop in the environment and then find a host to burrow in their skin
(a)
Scabies is a disease that can:
occur in people who are immunocompromised but also in those with weaker immune systems
cause thick crusts on the skin that can harbour thousands of mites
occur in over-crowded environments
all are true
none are true
Infection with Group A Streptococcus (GAS) bacteria during scabies is facilitated by:
burrowing of the mite into the skin
scratching to relieve itchiness
dampening of the host immune system by scabies
all of the answers are true
none of the answers are true
Two bacterial infections that commonly co-occur with scabies infection are:
E. coli, Staphylococcus epidermidis
Streptococcus pyogenes, E. coli
Streptococcus pyogenes, Staphylococcus epidermidis
MRSA, Staphylococcus epidermidis
Streptococcus pyogenes, MRSA
Which group of protozoans has species that are solely parasitic?
flagellates
ciliates
apicomplexa
amoebae
none of these, all groups include species that are free-living
A classic diagnostic feature of Giardia spp. in the trophozoite stage is?
presence in the blood
rash on skin where cercaria have breached the epithelium
presence of four visible nuclei
presence of two visible nuclei
the cell has a light right around it
Shortly after Taxoplasma gondii invades the host, it differentiates into a form called
bradyzoite
tachyzoite
oocyst
cyst
none of these
Toxoplasma gondii can reproduce sexually in the following host/hosts:
cat
mouse
human
pig
all of these
Which of the following Toxoplasma gondii life stages are infectious?
bradyzoites
tropozoites
oocysts
all of these answers
none of these answers
T or F. The two main assemblages of arachnids are ticks and mites
(a)
Select all that are correct about Sarchoptes scabiei
parasitic mite infection
close personal contact
infects skin
circular mites with short legs
scratching and rash
T or F. Crusted scabies occurs in immunocompromised individuals
(a)
Select all that are correct about scabies in humans
burrow in epidermis
females mate once
males bigger
cause secondary infections (group A strep)
diseases: acute rheumatic fever, rheumatic heart disease, renal failure
T or F. S. pyogenes is the most common group A strep bacteria
(a)
What is the diagnosis of scabies?
clinical features of skin
mite
eggs
fecal pellets
negative blood results
What are the four protozoa groups?
ciliates
amoebae
flagellates
sporozoa
toxoplasma
T or F. The trophozoite phase of protozoa is replication inside human hosst by budding or binary fission
(a)
T or F. In the cyst phase of protzoa, there is a production of a resistant cyst form of cell which reduces drying out
(a)
T or F. Giardia intestinalis are flagellates that are found in the liver
(a)
What are the consequences of gut epithelial dysfunction?
malabsorption of glucose, sodium, and water
reduced disaccharidase activity
increased intestinal permeability
gain of epithelial barrier fuction
What are the diagnosis' of protozoa in trophozoite stage?
pear shaped
motile
sucking disk on ventral surface
eight flagella
three median bodies
T or F. Toxoplasmosis cannot cause damage to brain, eyes or other organs
(a)
Toxoplasma infections are acquired via
cats
oocyst ingestion
transplacental
raw milk of animals
dogs
What is the diagnosis of toxoplasmosis?
retinal examination
measuring IgG and IgM
direct observation of parasite
blood test
