Parisitology

Question 1

Define parasite

Answer 1

An organism that lives in or on another to its own advantage and to the disadvantage of the host

Question 2

What is an obligate parasite - give 1 example

Answer 2

The parasite cannot complete their lifecycle without exploiting a host
Tapeworm

Question 3

What is a facultative parasite - give 1 example

Answer 3

Organism is not normally parasitic but enters host accidently
Free-living nematode

Question 4

What is an accidental parasite - give 1 example

Answer 4

When a parasite enters the body of a species different from its normal one
Nematode

Question 5

What is an opportunistic pathogen

Answer 5

One that only causes severe disease in immune-deficient hosts

Question 6

What is a definitive host

Answer 6

Host in which the parasite reaches sexual maturity

Question 7

What is an intermediate host

Answer 7

Host required for completion of lifecycle but parasite cannot reach sexual maturity

Question 8

What is a reservoir host

Answer 8

An animal that harbours infection that can be transmitted to humans

Question 9

What is a direct lifecycle

Answer 9

Parasite completes life cycle in a single host

Question 10

What is an indirect lifecycle

Answer 10

Multiple hosts or involvement of a vector

Question 11

Give 2 examples of arthropod parasites

Answer 11

Ticks - Lyme disease
Salmon louse

Question 12

What are Schistosoma better known as - what do they cause

Answer 12

Blood flukes
Schistosomiasis

Question 13

The parasite produces eggs in the gut that hatch externally in fresh water - what do the eggs release

Answer 13

Miracidia

Question 14

What do the Miracidia then produce once they have infected a snail

Answer 14

Tailed cercariae

Question 15

The cercariae burrow through human skin and goes undetected in the human body until they reach the liver - How?

Answer 15

The parasite covers itself in human proteins

Question 16

Give a stage 1,2 and 3 symptom of schistosomiasis

Answer 16

(1) Blood in faeces
(2) Inflammation of abdomen
(3) Bladder cancer

Question 17

What drug is used to remove the covering of human proteins on the parasite

Answer 17

Praziquantel

Question 18

What does lymphatic filariasis cause

Answer 18

Elephantiasis due to blockage of lymph nodes

Question 19

What does the drug used to treat L. filariasis do - what else can be done when a person is infected

Answer 19

Sterilises the adults
Regular washing to reduce secondary infection

Question 20

What are the 4 protozoan parasite classes

Answer 20

Flagellates
Amoebas
Sporozoa
Ciliates

Question 21

What is a trophozoite

Answer 21

Vegetative state in the lifecycle of a parasite

Question 22

What is the name of the most deadly form of malaria

Answer 22

Plasmodium falciparum

Question 23

What kind of mosquito is responsible for malaria

Answer 23

Female Anopheles

Question 24

What is released into the circulation when one is bitten and where do they go

Answer 24

Sporozoites
To the liver

Question 25

When the sporozoites have increased in number what happens to the cells - what is released

Answer 25

The liver cells burst Merozoites are released

Question 26

What do the merozoite infect - what do they turn into

Answer 26

Red blood cells Trophozoites

Question 27

What do the trophozoites form into and where do these go

Answer 27

Gametocytes Taken back up by mosquito

Question 28

What occurs in the mosquito to circle back to sporozoites

Answer 28

Fertilisation to form a haploid zygote which undergoes meiosis to form the haploid Oocyst

Question 29

Give 2 symptoms of malaria

Answer 29

Flu-like Amaemia

Question 30

What stain is used to examine blood cells in parisitology

Answer 30

Giemsa

Question 31

What doe Leishmaniasis grow in and give 1 detail on morphology

Answer 31

Macrophages Flaggellated

Question 32

1 detail on cutaneous, mucocutaneous and visceral leishmaniasis

Answer 32

C - form nodules and ulcers on the skin M - destruction of mucous membranes in mouth, nose and throat V - enlargement of liver/spleen

Question 33

What is the vector for leishmaniasis

Answer 33

Sandfly

Question 34

What does T. brucei cause, what does it produce and what is the vector

Answer 34

African sleeping sickness - tsetse fly - tryptophan

Question 35

What does T. cruzi cause, what part of the body does it affect and what is the vector

Answer 35

Chagas disease - heart - kissing bug

Question 36

What are the two stages of the Entamoeba histolytica parasite

Answer 36

Cyst and Trophozoite

Question 37

What is 1 symptom of E. histolytica

Answer 37

Dysentery

Question 38

Give 1 detail on morphology of Giardia intestinalis parasite - what must be ingested to become infected

Answer 38

Flagellated - resistant cyst

Question 39

Give 1 symptom of G. intestinalis

Answer 39

Explosive diarrhoea