Brainscape's Knowledge GenomeTM

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


See full index

Human Parasitology > Toxoplasma gondii > Flashcards

Toxoplasma gondii Flashcards

1
Q

What are the 2 stages in the life cycle of T. gondii?

A
  1. intestinal epithelium

2. extrainstestinal

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

In which hosts do the 2 stages occur?

A
  1. intestinal epithelium - cats & other felines

2. extra intestinal - cats & other hosts

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

Which is the sexual stage?

A

intestinal epithelium

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

What stages of the parasite are infective to cats?

A

oocyst or pseudocyts

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

Trace the development of the parasite through the intesitnal epithelial stage.

A
  1. cat ingests oocyst or pseudocyst
  2. invades intestinal epithelial cell
  3. develops into troph
  4. schizogony
  5. merizotes lyze host cell & invade other peithelial cells -> several generations
  6. some trophs undergo gametogony: macro or microgamete
  7. fertilization -> oocyte
  8. immature oocyst escapes epithalial cell -> shed in feces
  9. sporogony -> mature oocyst
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What happens during schizogony?

A

Production of 2-40 merozoites

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

Where does gametogony occur & what is produced?

A

production of micro or macrogamete

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

What stage is produced from fertilization?

A

oocyst

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

What occurs during sporogony

A

mature oocyst is produced

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

Describe a mature oocyst.

A

2 sporocysts

4 sporozoites

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

In what hosts does the extra intestinal stage occur?

A

cats & other hosts

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

What stages of the parasite are infective to the host?

A

oocyst or pseudocyst

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Trace the development of the parasite in the host. (extraintestinal)

A
  1. host ingests oocyst or pseudocyst
  2. penetrates intestine & taken up macrophage
  3. spreads through body
  4. multiplies rapidly in macrophages & lymph tissue -> tachyzoites
  5. invade other cells
  6. immune response
  7. bradyzoite -> multiply rapidly
  8. psuedocyst
  9. predation
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Do schizogony or gametogony occur in extraintestinal stage?

A

no

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

Describe a major difference between tachyzoites and bradyzoites. What is the cause of this difference?

A

bradyzoites - multiply slowly
tachyzoites - multiply rapidly
Allows bradyzoites to survive in the pseudocysts from months to years as long as the immune system is good

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

What is a pseudocyst?

A

intracellular
Large clumps of bradyzoites
mothers/yrs
as long as immunity intact

17
Q

How is the parasite transmitted to the next host?

A

predation

18
Q

What type of host is most likely a dead end in this life cycle?

A

-

19
Q

Describe the acute and chronic stages of infection in humans. Is the parasite multiply quickly or slowly?

A

acute - painful & swollen lymph nodes, fever, headaches, muscle pain, lesions in brain, eye, heart, lungs, rarely causes death
chronic - asymptomatic, sometimes pseudocysts: in eye = blind spot, in brain = paralysis
quickly

20
Q

Where in the body is the parasite found in the acute or chronic stages?

A

eyes and brain

21
Q

What problems can be cause by pseudocysts?

A

blind spot in eye

paralysis if in brain

22
Q

What happens in a n immunocompromised host?

A

parasite multiplies very rapidly

23
Q

Give some examples of medical conditions in which infection with Toxoplasma could be a problem.

A

AIDS - opportunistic infection

chemotherapy patients

24
Q

What is congenital toxoplasmosis?

A

mother contract toxo during 1st trimester
fetus has no immune response
10% die, 30% severe complications: hydrocephaly, impaired mental development

25
Q

How does the fetus become infect w/ cognenital toxo and why is it so severely affected?

A
  • Crosses over into the developing fetus
  • Fetus has no immune response to contain the parasite host
  • Hydroencephaly
26
Q

How can infection with toxo be dignosed?

A

ELISA - antibody in blood

detection of toxo DNA in amniotic fluid

27
Q

What is the mechanism of action in pyrimethamine?

A

blocks folic acid production

28
Q

How can infections be controlled?

A
  • cat: hunt -> infects w/ oocysts in litterbox/sandbox
  • meat prep: beef tartar
  • food storage: files &cockroaches can carry oocysts
  • obstetrician recommendations: no cats, don’t change litter, no raw meat

Human Parasitology (22 decks)

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