CAR Parasitology

Question 1

what is parasitism

Answer 1

only one organism benefits from the interaction but to the detriment of the other

Question 2

what is mutualism

Answer 2

organisms of different species both benefit from the interaction

Question 3

what is commensalism

Answer 3

only one organism benefits from this association without causing any harm to the second organism (clown wish and anemone)

Question 4

list the 4 types of parasites and define them

Answer 4

• facultative: may survive in the absence of the host
• obligate: at some or all stages of the life cycle, cannot survive in the absence of the host
• endo-oarasite: lives internally inside the host
• ecto-parasite: lives in/on the outer body surfaces of the host

Question 5

list the types of hosts and define them

Answer 5

• definitive: the host in which the parasite sexual reproduction occurs
• intermediate host: the host in which parasite asexual reproduction occurs
• permissive host: not usually used by parasite but still favours life cycle completion
• non-permissive host: host in which the parastie cannot complete the life cycle
• reservoir host: temporary host used in abesnce of natural host
• paratenic host: host the parasite without any further development

Question 6

what is a mechanical vector vs biological vector

Answer 6

• mechiancal vector: a vector which mechanically spreads parasite and is not utilised in the parasite life cycle
• biological vector: a vector needed by the parasite to complete part of its life cycle

Question 7

how are parasites spread to a new host

Answer 7

• ingestion of infective stage
• skin penetration by infective stage
• skin inoculation by insect bite
• direct animal to animal contact
• trans placental
• sexual intercourse
• inhalation

via: food, water, soil, airborne, vector borne, mother to fetus

Question 8

what is a direct parasite life cycle

Answer 8

parasitic stages develop in/on 1 host

Question 9

what is an indirect parasite life cycle

Answer 9

intermediate host is needed for the development of some stage of the parasite

Question 10

what information is important to know about the life cycle of a parasite

Answer 10

• type of life cycle
• who serves as definitive host
• who serves as intermediate host
• what is the infective stage
• what is the route of infection