Chapter #15 Q's: Parasitism and Mutualism
The change of a biological object triggered by the range of a related object
Coevolution
One species benefits while the other is largely unaffected
Commensalism
__________ occurs when the host population density is high and can sharply reduce the host population
Outbreaks
A mutualism in which two species benefit when living together but can survive when apart is referred to as a(n)
facultative mutualism
A lichen is a commensalistic relationship between a fungus and an alga.
false
Animal parasites can be either ecto- or endoparasites, whereas all plant parasites live inside the plant tissue as endoparasites.
false
Most nonsymbiotic mutualisms are obligatory.
false
Mycorrhizae are nitrogen-fixing bacteria living within the roots of certain tropical trees.
false
Myrmechochores are ants that are attracted to the seeds of certain plants.
false
Nitrogen is important in the mutualism between legume plants and Rhizobium bacteria.
false
Parasites always complete their life cycle in a single host species.
false
Parasites are always transmitted between hosts via an intermediate vector organism.
false
Parasites typically impact host survival but not reproduction.
false
Plants do not benefit from insects that prey on their nectar.
false
Preening by birds is an example of an inflammatory response to infection.
false
Symbiosis is an interaction between two species that is beneficial to both species
false
The number of parasites per individual is relatively high in most individuals and low in a few individuals.
false
Plants often react to attacks on their leaves, stems, fruit, or seeds by forming abnormal structures called ________.
galls
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.
immune
An animal that feeds upon nectar is referred to as a(n) ________.
nectivore
Explain how parasites may impact the survival, reproduction, and population size of their hosts.
parasites take their host's resources, and can inhibit their growth
When infected by a parasite, an animal typically
produces fewer offspring than a healthy individual.
The intimate and protracted association between two or more organisms of different species is referred to as
symbiosis
Which of the following is a macroparasite?
tick
Which of the following is an ectoparasite?
tick that attaches to the skin
The host species in which a parasite becomes an adult and reaches maturity is referred to as a(n) ________ host.
definitive
The mutualistic algae that live within the tissues of corals are called ________.
zooxanthellae
Behavioral defenses may help a host avoid infection are...
Grooming and location
Relatively large parasites, such as viruses, bacteria, and protozoans, are referred to as ________.
macroparasites
The mutualistic fungi that can live within the roots of certain plants are called ________.
mycorrhizae
Explain how parasitism differs from mutualism and what the distinction is between an infection and a disease.
- one is harmed - the infection is when the parasite grows in your body. Disease is when the infection begins to damage the host cells.
Describe two examples of defensive mutualisms.
Anenome and Clownfish Acacia Ants and Acacia plants
________ transmission occurs when a parasite is transferred from one host to another without the involvement of an intermediate organism.
Direct
__________Mutualists can survive and reproduce without the interaction
Facultative
Hosts respond to parasitic invasions by....
Inflammatory response and internal cysts
Some parasites are transmitted between hosts by an intermediate vector often an arthropod
Intermediate vector
________ is a disease caused by protist parasites. The vector is a female mosquito
Malaria
The relationship becomes beneficial to both host and parasite
Mutualism
Mutualists cannot survive or reproduce without the interaction
Obligate
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.
TRUE
_________ transmission is the transmission of parasites from mother to offspring just before or just after birth
Vertical
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
an inflammatory response
Describe the potential benefits of pollination between a plant and a pollinator.
both species benefit how??
The most debilitating external parasites of birds and mammals are spread by
direct contact
Microparasites are usually characterized by
direct transmission from one host to another.
The outcome of an infection is called a(n) ________.
disease
Parasites that live on the skin of their host are called ________.
ectoparasites
Plants that rely on ants to disperse their seeds have an ant-attracting food body on the seed coat referred to as a(n) ________.
elaiosome
Which of the following is a potential response by a plant host to a parasite?
formation of a gall
A lichen consists of a(n) ________ and an alga (or, in some cases, a cyanobacterium).
fungus
Plant parasites that are photosynthetic but draw water and nutrients from their host plant are referred to as
hemiparasites
A heavy load of parasites is termed a(n) ________.
infection
After infection occurs, the first line of defense for a host against a parasite is the ________ response.
inflammatory
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.
intermediate
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)
intermediate host
Which of the following symbiotic mutualisms involves a fungus?
lichens
Describe two examples of mutualisms involving the transfer of nutrients.
lichens birds and mammals
A relationship between two species in which both species benefit is called ________.
mutualism
Explain how the consumption of seeds or fruit by an animal could result in either parasitism or mutualism.
mutualism- spreading the seeds
Which of the following mutualisms is a cleaning mutualism in which one species removes ectoparasites from another?
oxpeckers and large mammals
A(n) ________ lives on or within the host organism for some period of its life.
parasite
Discuss the differences between direct and indirect transmission of a parasite.
the use of a vector
A major problem for parasites is gaining access to and escaping from the host.
true
Holoparasites are plants that lack chlorophyll and are thus nonphotosynthetic, relying totally on a host's tissues for nutrition.
true
In a commensalistic relationship between two species, only one species benefits without significantly affecting the other.
true
In mutualism, the interaction between two species is more often a reciprocal exploitation than a cooperative effort between individuals.
true
Microparasites are usually transmitted directly from one host to another.
true
Nectar is often produced by plants as an enticement or reward for pollinating animals.
true
Parasites may regulate host populations.
true
Plants benefit from frugivores, which aid in the dispersal of their seeds.
true
Some parasitic plants are spread from one plant to another by direct transmission.
true
Some symbiotic mutualisms involve defense against herbivores.
true
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.
true
The relationship between ants and acacias represents a defensive mutualism.
true
Zooxanthellae are photosynthetic algae living within the tissues of reef-forming corals.
true
Some parasites are transmitted between hosts by an intermediate organism, or ________.
vector
