Parasite

Question 1

Define “parasite”?

Answer 1

Animals or plants who live on or in others from which they obtain nutrition

Question 2

What are the 3 main types of parasite?

Answer 2

Helminths
Protozoa
Arthropods

Question 3

What is a protozoa?

Answer 3

A microscopic unicellular organism

Question 4

Can protozoa live independtly?

Answer 4

Protozoa can live free of a host

Question 5

How do protozoa travel between human hosts?

Answer 5

Those in the human intestine travel there by the faecal-oral route.
Those in the blood/tissue travel there by an arthropod vector.

Question 6

Can protozoa multiply in humans?

Answer 6

Yes, protozoa multiply in humans

Question 7

What protozoa causes malaria?

Answer 7

4 plasmodium species

P. Falciparum is the most deadly

Question 8

What is the vector for the plasmodium species that cause malaria?

Answer 8

Anopheles Mosquito Vector

Question 9

In what form are plasmodium species injected under the skin by mosquitos?

Answer 9

As sporozoites

Question 10

How do sporozoites mature?

Answer 10

They travel through blood to liver where they mature into merozoites

Question 11

What do merozoites do in the body to cause malaria?

Answer 11

Invade & destroy RBCs, using them to multiply

Question 12

What causes Amoebic Dysentery?

Answer 12

The protozoa: Entamoeba Histolytica

Question 13

What are the effects of AMoebic Dysentery?

Answer 13

• Protozoal Cysts in stool
• Late disease Liver abscesses
• Diarrhoea with blood/pus

Question 14

What does Entamoeba Histolytica do to RBCs?

Answer 14

Ingests them by Pseudopodia

Question 15

What causes Leishmaniasis?

Answer 15

Leishmania Species

Question 16

What are the sub-types of Leishmaniasis?

Answer 16

Cutaneous & muco-cutaneous

Question 17

What do the sub-types of leishmaniasis cause?

Answer 17

Skin & mucosal Ulcerations

Question 18

What does Visceral Leishmaniasis cause?

Answer 18

• Fever
• Weight loss
• Hepato-Splenomegaly

Question 19

How are Leishmania transmitted?

Answer 19

By Sandfly Bites.

Question 20

What are 3 types of Helminths?

[Hint: Sellotape & tremors]

Answer 20

Nematodes (Roundworms)
Trematodes (Flatworms)
Cestodes (cellotape)

Question 21

How do Nematodes reach the Small intestine?

Answer 21

• Eggs ingested & enter Blood
• Egs hatch & enter lungs
• Lungs -> stomach -> Small intestine

Question 22

What can Nematodes cause?

Answer 22

• A mass of worms can block bile duct

- Loefllers Syndrome (accumulation of eosinophils in lungs)

Question 23

How are nematodes diagnosed?

Answer 23

Ova are seen in the Stool sample microscopy

Question 24

How are Trematodes diagnosed?

Answer 24

Ova can be seen in the faeces & urine

Question 25

How do trematodes hatch?

Answer 25

In fresh water as miracidia

Question 26

Where do trematodes mature?

Answer 26

In the bodies of snails (intermediate hosts)

Question 27

What is an adult trematode called?

Answer 27

Cecaria

Question 28

How trematodes reach the liveR?

Answer 28

Penetrate human skin.

Then migrate from Lungs -> Liver.

Question 29

At what point to nematodes mature into adult roundworms?

Answer 29

In the stomach before entering the small intestine