Deck 15: Parasitism and Mutualism

Question 1

A species that interacts with many other species rather than only a few, such as a nectivore that gathers nectar from many plant species, is called a ________.

Answer 1

generalist

Question 2

After infection occurs, the first line of defence for a host against a parasite is the ________ response.

Answer 2

inflammatory

Question 3

A relationship between two species in which both species benefit is called ________.

Answer 3

mutualism

Question 4

The ________ host is the host species in which a parasite becomes an adult and reaches maturity.

Question 5

Relatively small parasites, such as viruses, bacteria, and protozoans, are referred to as ________-parasites.

Question 6

Parasites that live within their host rather than on the skin are referred to as ________-parasites.

Question 7

A relationship between two species in which one species benefits and the other is not significantly affected is called ________.

Question 8

An outbreak of canine distemper occurred in Toronto in 2010. Briefly explain why this may have happened and what the outcome was.

Question 9

The outcome of an infection is called a(n)________.

Question 10

A(n)________ is an intermediate organism that aids the spread of a parasite from one host to another.

Question 11

The ________ host is a host species that harbors a developmental stage of a parasite, but in which the parasite does not reach maturity.

Question 12

A ________ lives on or within the host organism for some period of its life.

Question 13

________ is the intimate and protracted association between two or more organisms of different species.

Question 14

Parasites that live on the skin of their host are called ________-parasites.

Question 15

Plants often react to attacks on the leaf, stem, fruit, or seed by forming abnormal structures called ________.

Question 16

When a foreign object, such as a virus or bacterium, enters the bloodstream, it elicits a(n)________ response.

Question 17

The mutualistic fungi that can live within the roots of certain plants are called ________.

Question 18

A heavy load of parasites is termed a(n)________.

Question 19

________ transmission is the transfer of a parasite from one host to another without the involvement of an intermediate organism.

Question 20

In a ________ mutualism, an animal transfers pollen from one plant to another in exchange for some reward such as nectar.

Question 21

Microparasites are relatively small, including organisms such as flatworms, flukes, lice, fleas, and ticks.

Question 22

Which of the following symbiotic mutualisms involves a fungus?

A)lichens
B)legume-Rhizobium interactions
C)corals and zooxanthellae
D)gut microbe-ruminant interactions

Question 23

Plants that rely on ants to disperse their seeds are called ________.

Question 24

The intimate and protracted association between two or more organisms of different species is referred to as a

A)mutualism.
B)parasitism.
C)commensalism.
D)symbiosis.

Question 25

The most debilitating external parasites of birds and mammals are spread by

A)a vector.
B)an intermediate host.
C)a definitive host.
D)direct contact.

Question 26

Pre-agricultural humans were mostly bothered by ________ parasites.

A)viral
B)bacterial
C)uncommon
D)macro-

Question 27

A major problem for parasites is gaining access to the host.

Question 28

A mutualism in which two species must live together and cannot survive when apart is referred to as a(n)

A)obligatory mutualism.
B)trophic mutualism.
C)dispersive mutualism.
D)facultative mutualism.

Question 29

A host species that harbors only a developmental phase of a parasite is called a(n)

A)intermediate host.
B)direct host.
C)definitive host.
D)macrohost.

Question 30

When infected by a parasite, an animal typically

A)grows more rapidly than a healthy individual.
B)produces fewer offspring than a healthy individual.
C)behaves less conspicuously than a healthy individual.
D)is less likely to be preyed on than a healthy individual.

Question 31

Which of the following is an ectoparasite?

A)virus that inhabits the lymphatic system
B)bacterium that attacks the brain
C)tick that attaches to the skin
D)fluke that inhabits the bloodstream

Question 32

Symbiosis is an interaction between two species that is beneficial to both species.

Question 33

A heavy load of parasites is called a(n)

A)infection.
B)disease.
C)macroparasitism.
D)parasitoidism.

Question 34

Plant parasites that are photosynthetic but draw water and nutrients from their host plant are referred to as

A)mycorrhizae.
B)vectors.
C)parasitoids.
D)hemiparasites.

Question 35

Which of the following is a potential response by a plant host to a parasite?

A)formation of a gall
B)allelopathy
C)production of lymphocytes
D)growing more rapidly

Question 36

Which of the following is likely to be the first response of an animal host to a new parasite?

A)formation of a cyst
B)allelopathy
C)inflammatory response
D)immune response

Question 37

Which of the following is a microparasite?

A)virus
B)flea
C)fluke
D)mistletoe

Question 38

The killing of raccoons through a distemper outbreak represents a ________ response.

A)density dependent
B)density independent
C)predator-prey
D)immune

Question 39

Briefly outline the relationship between whitebark pine blister rust and the dispersal and regeneration of whitebark pine trees.

Question 40

Which of the following types of mutualisms is a defensive mutualism?

A)corals and zooxanthellae
B)bees and flowers
C)ants and acacias
D)birds and fruits

Question 41

Some symbiotic mutualisms involve defence against herbivores.

Question 42

A lichen is a symbiotic mutualism between a fungus and an alga.

Question 43

Direct transmission of a parasite involves an intermediate organism known as a vector.

Question 44

An immune response is triggered when a foreign object, such as a virus or bacteria, enters the bloodstream.

Question 45

Symbiotic mutualisms usually involve the exchange of services such as pollination or seed dispersal.

Question 46

The relationship between ants and acacias represents a pollination mutualism.

Question 47

In a mutualistic relationship between two species, both species benefit.

Question 48

Mycorrhizae are nitrogen-fixing bacteria living within the roots of certain tropical trees.

Question 49

Parasites typically impact host survival but not reproduction.

Question 50

Parasites are always transmitted between hosts via an intermediate vector organism.

Question 51

In a mutualism, the interaction between two species is often more a reciprocal exploitation than a cooperative effort between individuals.

Question 52

After infection occurs, the first line of defence by a host against invasion of a parasite is an inflammatory response.

Question 53

Animal parasites can be either ecto- or endoparasites, whereas all plant parasites live inside the plant tissue as endoparasites.

Question 54

Zooxanthellae are algae living within the tissues of reef-forming corals.

Question 55

The number of parasites per individual is relatively high in most individuals and low in a few individuals.

Question 56

Nitrogen is important in the mutualism between legume plants and Rhizobium bacteria.

Question 57

In a commensalistic relationship between two species, both species benefit.

Question 58

Hemiparasites are plants that do not conduct photosynthesis because they obtain water and nutrients from another host plant.

Question 59

Parasites may regulate host populations.

Question 60

Parasites always complete their life cycle in a single host species.

Question 61

What is the difference between parasitism and mutualism?

Question 62

Plants do not benefit from insects that prey on their nectar.

Question 63

Nectar is often produced by plants as an enticement or reward for pollinating animals.

Question 64

Whitebark pine rust can reduce the number of Clark's nutcrackers in a given habitat.

Question 65

Describe one pre-infection and two post-infection responses that animal hosts might have to parasites.

Question 66

Draw a graph that illustrates the impact of one species on the carrying capacity of another according to the Lotka-Volterra models of mutualism.

Question 67

Discuss the difference between mutualism and commensalism.

Question 68

Plants benefit from frugivores, which aid in the dispersal of their seeds.

Question 69

Use an example to illustrate the fact that parasites can impact both the survival and reproduction of their hosts.

Question 70

The simple Lotka-Volterra models for mutualism describe the dynamics of an obligate interaction in which neither species can survive and reproduce in the absence of the other.

Question 71

Give two examples of mutualisms involving the transfer of nutrients.

Question 72

Explain how the consumption of seeds or fruit by an animal could result in either parasitism or mutualism.

Question 73

Discuss the potential benefits of pollination between a plant and a pollinator.

Question 74

Explain the potential benefit to a plant of having either ants or fungi living in its tissues.

Question 75

Discuss the differences between direct and indirect transmission of a parasite.

Question 76

How might a plant respond to invasion by a fungal or bacterial parasite?

Question 77

Discuss how the production and dispersal of seeds by plants may represent a mutualism between two species.

Question 78

Give two reasons that it can be difficult to detect the effects of mutualism on the population dynamics of species.

Question 79

Myrmecochores are plants that attract ants to their seeds.

Question 80

Describe the relationship between mycorrhizal associations with Cerastium and pollination as identified in the Cahill and Elle studies.