Unit 2 - Topic 5 - Parasitism - Section C - Transmission and Virulence

Question 1

What is transmission

Answer 1

The spread of a parasite to a host

Question 2

What is virulence

Answer 2

The harm caused to a host species by a parasite

Question 3

How are ectoparasites generally transmitted

Answer 3

Through direct contact

Question 4

How are endoparasites of the body tissues often transmitted

Answer 4

By vectors or by consumption of intermediate hosts

Question 5

What are factors that increase transmission rate

Answer 5

Overcrowding of host when they are at high density, and mechanisms, such as vectors and waterborne dispersal stages, that allow the parasite to spread even if infected hosts are incapacitated

Question 6

How can host behaviour be effect by parasites

Answer 6

Host behaviour is often exploited and modified by parasites to maximise transmission

Question 7

Examples of modifications to host behaviour include

Answer 7

Alteration of host foraging, movement, sexual behaviour, habitat choice or anti-predator behaviour.

Question 8

What becomes part of the extended phenotype of the parasite

Answer 8

Host behaviour

Question 9

What do parasites often do to the host that benefit the parasites growth, reproduction or transmission

Answer 9

Suppress the host immune system and modify host size and reproductive rate