Parasitology

Question 1

2 major groups of parasites

Answer 1

1. Protozoa (unicellular) - microscopic, free living or parasitic, multiply in humans
2. Helminths (multicellular) - larger, parasitic, the “worms”

Question 2

Intermediate Host

Answer 2

Used during part of parasite life cycle, completes part of a parasites developmental stage, multiplies asexually but not sexually
*usually insect or animal

Question 3

Definitive Host

Answer 3

Matures the parasite, parasite multiplies sexually

*usually humans

Question 4

Nocturnal Periodicity

Answer 4

Periodic migration of microfilariae btwn peripheral blood and lung capillaries
* influences most appropriate sampling time to increase chance of detection

Question 5

3 main pathogenic mechanisms of parasitic infections:

Answer 5

• Toxic products
• Mechanical tissue damage
• Immunopathology

Question 6

Top 4 parasites worldwide?

Answer 6

1. Giardiasis
2. Toxoplasmosis
3. Ascariasis
4. Hookworm