Toxoplasma

Question 1

What is the superphylum of toxoplasma?

Answer 1

Alveolata

Question 2

Cortical alveoli or inner membrane complex.

It is a flattened membranous cristernae underlying the plasma membrane

Answer 2

Alveolata

Question 3

mitochondria with tubular christae

Answer 3

alveolata

Question 4

Many are photosynthetic. It has a transverse flagellum that encircles th body and a longitudinal flagellum oriented perpendicular

Answer 4

Dinoflagellata

Question 5

some or all of
the surface is covered with
short, dense hairlike
structures (cilia) which
beat to propel the ciliate
through the water and/or to
draw in food particles

Answer 5

ciliata

Question 6

Diverse group. All parasitic.
Elements of the Apical
complex

Answer 6

Apicomplexa

Question 7

an
assemblage of
cytoskeletal elements
and secretory
organelles
 No flagella or cilia
except for the
microgamete (sperm)
 All members of the
phylum are parasitic

Answer 7

Apical Complex

Question 8

Reproduction: Apicomplexa

Answer 8

both asexual and sexual

Question 9

parasites of invertebrates,
some quite big (used as early research
models), Cryptosporidium might belong into
this category

Answer 9

Gregarines

Question 10

small
parasites of blood cells which are
transmitted by arthropods

Answer 10

Haemosporidians (Plasmodium) and

Piroplasms (Babesia & Theileria

Question 11

tissue parasites of vertebrates
and invertebrates (can have single (e.g.
Eimeria) or two hosts (e.g. Toxoplasma).

Answer 11

Coccidians

Question 12

Initially found in 1908 as a tissue parasite of gondi (an african rodent)

Answer 12

Toxoplasma gondii

Question 13

High prevalence in Europe. In the

US approx. 20-50% of the population is infected

Answer 13

Toxoplasma gondii

Question 14

Transmission by tissue cysts (containing bradyzoites) or the oocyst
(containing sporozoites)
• Infection through ingestion of undercooked or raw
meat or contaminated water

Answer 14

Toxoplasma gondii

Question 15

Parasite form

Answer 15

Tacgyzoites
Bradyzoites
Tissue Cysts
Oocysts
"TBTO" Throw back Thursday only!

Question 16

rapidly growing meront or zoite observed in the early

stage of of infection

Answer 16

Tachyzoites

Question 17

Slow-growing zoite or meront inside the tissue cysts

Answer 17

Bradyzoites

Question 18

Found in the tissues, contain bradyzoites. Infective form

Answer 18

tissue cyst

Question 19

Zygote forn and highly resistant form. This is also an infective form:
sporocyst or sporozoites

Answer 19

Oocysts

Question 20

Life cycle of toxoplasma gondii

Answer 20

Ingestion of TG by car
Oocysts are produced and excreted in the feces.
Sporulation results in the formation of sporozoites
sporulated oocyst remain infective for months
intermediate host gets contact with the cyst.

Question 21

How do they multiply?

Answer 21

endodiogeny

Question 22

What are the sources of infection for toxoplasma?

Answer 22

Contaminated water or
food
Undercooked meat
Mother to fetus
Organ transplant (rare)
Blood transfusion (rare)

Question 23

The acute infection is carried by which stage?

Answer 23

Tachyzoite stage

Question 24

These divide rapidly and aggressively destroy tissues. These can also cross the blood brain barrier and the placenta.
Crescent shaped
• 2 by 6 μm
• Asexual form
• Multiplies by endodyogeny
• It can infect phagocytic and nonphagocytic,
nucleated cells.

Answer 24

Tachyzoites

Question 25

Are resistant to all currently available drugs

Answer 25

Bradyzoites

Question 26

Bradyzoite cysts are highly infective if

Answer 26

INGESTED

Question 27

This mark the beginning of the chronic phase

Answer 27

bradyzoite stage

Question 28

are resistant to low pH and digestive enzymes durinfg stomach passage

Answer 28

bradyzoites

Question 29

Three situations can lead to severe diseases

Answer 29

1) congenital toxoplasmosis
2) occular toxoplasmosis in immunocompetent adults
3) loss of a functional immune system

Question 30

acute infection of the expectant mother.
Severity depends on the stage of pregnancy.
Spontaneous abortions or neurological disorders such as
blindness and mental retardation can result.

Answer 30

Congenital disease

Question 31

Pregnancy and toxoplasmosis

Answer 31

If a women is infected for the first
time during pregnancy the parasite
can transverse the placenta and
cause fetal disease

Question 32

Only 25-30% of seropositive patients who develop AIDS develop TE
• Involvement of the CNS.
• Symptoms: lethargy, loss of memory to severe dementia, focal to major
motor seizures

Answer 32

Toxoplasmic encephalitis

Question 33

What happens to the eye if it gets infected by the parasite toxoplasma?

Answer 33

ocular toxoplasmosis

Question 34

Diagnosis of toxoplasmosis

Answer 34

Parasites can be detected in biopsied specimens or cerebral spinal fluid.
Not very reliable.

Question 35

T or F: As all apicomplexa T. gondii only

replicates within cells

Answer 35

True

Question 36

T or F: The oocyst is noninfectious before sporulation.
• Unsporulated oocysts are subspherical to spherical and are 10 by 12
μm in diameter.

Answer 36

True

Question 37

Oocysts has two _______ ________

Answer 37

ellipsoidal sporocysts

Question 38

Prevention of tocoplasmosis

Answer 38

Avoid raw or undercooked meat. (Cooking kills Toxoplasma)
• Wash raw fruits and vegetables well before eating.
• Remove feces from the litter box every day, to eliminate any parasites before oocysts sporulate
• Keep cats indoors to prevent hunting. Cats can become infected by eating infected rodents or birds.
• Feed cats only commercial food or well-cooked meat.
• Do not feed cats raw or undercooked meat.
• Do not adopt cats who have lived outdoors or who have been fed raw meat.
• Do not handle stray cats.