Deck 16: Parasitism and Mutualism

Question 1

A lichen consists of a(n)________ and an alga (or,in some cases,a cyanobacterium).

Answer 1

fungus

Question 2

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

Answer 2

parasite

Question 3

The mutualistic algae that live within the tissues of corals are called ________.

Answer 3

zooxanthellae

Question 4

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

Question 5

A host species that harbors a developmental stage of a parasite,but in which the parasite does not reach maturity,is referred to as a(n)________ host.

Question 6

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

Question 7

An animal that feeds upon nectar is referred to as a(n)________.

Question 8

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

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

Question 9

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

Question 10

Plants that rely on ants to disperse their seeds have an ant-attracting food body on the seed coat referred to as a(n)________.

Question 11

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

Question 12

The host species in which a parasite becomes an adult and reaches maturity is referred to as a(n)________ host.

Question 13

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

Question 14

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

Question 15

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

Question 16

Plants often react to attacks on their leaves,stems,fruit,or seeds by forming abnormal structures called ________.

Question 17

After infection occurs,the second line of defense for a host against a parasite,which is elicited when a foreign object,such as a virus or bacterium,enters the bloodstream,is referred to as a(n)________ response.

Question 18

Microparasites are usually characterized by

A)a large body size.
B)a long generation time.
C)a long time of infection relative to the host's expected life span.
D)direct transmission from one host to another.

Question 19

Some parasites are transmitted between hosts by an intermediate organism,or ________.

Question 20

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

Question 21

Microparasites are usually transmitted directly from one host to another.

Question 22

Preening by birds is an example of an inflammatory response to infection.

Question 23

Which of the following is a macroparasite?

A)virus
B)bacterium
C)tick
D)protozoan

Question 24

Holoparasites are plants that lack chlorophyll and are thus nonphotosynthetic,relying totally on a host's tissues for nutrition.

Question 25

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

Question 26

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 27

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

Question 28

Which of the following mutualisms is a cleaning mutualism in which one species removes ectoparasites from another?

A)corals and zooxanthellae
B)bees and flowers
C)ants and acacias
D)oxpeckers and large mammals

Question 29

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 30

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 31

A mutualism in which two species benefit when living together but can survive when apart is referred to as a(n)

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

Question 32

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 33

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

Question 34

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

A)formation of a gall
B)allelopathy
C)increased production of lymphocytes
D)more rapid growth of tissues

Question 35

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

Question 36

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

Question 37

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 38

Some parasitic plants are spread from one plant to another by direct transmission.

Question 39

A foreign object,such as a virus or bacterium,entering the bloodstream of a host and stimulating the production of antibodies is referred to as

A)allelopathy.
B)a behavioral response.
C)an inflammatory response.
D)an immune response.

Question 40

While foraging on grass,white-tailed deer occasionally ingest snails or slugs that host larvae of the meningeal worm.The worm larvae mature inside the deer and eventually are passed out with the feces.The snails acquire the larvae as they come into contact with deer feces on the ground.The snails are an example of a(n)

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

Question 41

In a commensalistic relationship between two species,only one species benefits without significantly affecting the other.

Question 42

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

Question 43

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

Question 44

Myrmechochores are ants that are attracted to the seeds of certain plants.

Question 45

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

Question 46

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

Question 47

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

Question 48

A lichen is a commensalistic relationship between a fungus and an alga.

Question 49

The formation of scabs on the skin and cysts in the muscles of animals in response to a parasite are examples of an inflammatory response.

Question 50

Most nonsymbiotic mutualisms are obligatory.

Question 51

The relationship between ants and acacias represents a defensive mutualism.

Question 52

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

Question 53

The Lotka-Volterra models used for competition may also be used to describe the dynamics of a mutualism by replacing the competition coefficients with positive interaction coefficients.

Question 54

Some symbiotic mutualisms involve defense against herbivores.

Question 55

Parasites may regulate host populations.

Question 56

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

Question 57

Parasites typically impact host survival but not reproduction.

Question 58

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