Deck 19: Symbioses

Question 1

Your large intestine is home to millions of bacteria that are able to digest plant material that could otherwise not be digested. Both you and the bacteria benefit from having access to material that would otherwise be unavailable. What kind of symbiosis is this?

A) parasitism
B) commensalism
C) altruism
D) mutualism

Answer 1

mutualism

Question 2

Anglerfish live deep in the ocean where very little light can penetrate. As their name suggests, they capture prey using a strategy of ambush. Their bait is a small 'lure' organ that contains luminescent bacteria, which they dangle just in front of their mouths. What kind of symbiotic relationship is exemplified by this example?

A) endosymbiosis
B) ectosymbiosis
C) parallel symbiosis
D) dysjunct symbiosis

Answer 2

endosymbiosis

Question 3

In endosymbiosis one organism lives inside another. Which of the following is an example of endosymbiosis?

A) an anemone fish and an anemone
B) a burdock (burr) and a furred animal
C) a tapeworm inside a human intestine
D) a monarch butterfly and a viceroy butterfly

Answer 3

a tapeworm inside a human intestine

Question 4

The alga Oophila amblystomatis live inside embryos of the spotted salamander (Ambystoma maculatum). The alga consumes the carbon dioxide produced by the embryo and provides it with oxygen. What type of relationship is this?

A) endosymbiosis
B) ectosymbiosis
C) autotrophy
D) parasitism

Question 5

Which of the following examples could be considered an example of mutualism?

A) lice living in human hair
B) a honeybee and a flowering plant
C) a tapeworm living within your digestive tract
D) a roundworm living within your dog's heart

Question 6

Which of the following terms best describes the relationship between a rose flower and the many species of insects that feed on its nectar and carry away pollen while doing so?

A) dispersive mutualism
B) diffuse mutualism
C) diffuse, dispersive mutualism
D) diffuse, trophic mutualism

Question 7

Blue jays eat seeds from a variety of tree species. The jays play an important role in dispersing these seeds, but also benefit from the high energy content of the seeds. Which of the following terms best describes the kind of symbiotic relationship that exists between the trees and the blue jays?

A) trophic mutualism
B) diffuse mutualism
C) dispersive mutualism
D) diffuse, dispersive mutualism

Question 8

Which of the following applies to determining that a symbiotic relationship is mutualistic?

A) There must be evidence for co-evolution.
B) There must be a benefit to both parties in the symbiosis.
C) There must be some form of mimicry.
D) There must be an effect on kin selection.

Question 9

The domestic cow houses many billions of bacteria in its rumen (stomach). With this arrangement, the bacteria gain access to the ingested plant material, which they digest and utilize. However, a waste product of the bacterial digestion is volatile fatty acids, which the cow absorbs and uses to support its own energy requirements. What is this relationship between the bacteria and the cow an example of?

A) parasitism
B) trophic mutualism
C) defensive mutualism
D) altruism

Question 10

A plant species provides nectar to, and can be pollinated by, multiple insect and hummingbird species. What kind of mutualism is this an example of?

A) Bayesian
B) diffuse
C) trophic
D) defensive

Question 11

Which of the following is an example of mutualism?

A) the monarch and Viceroy butterflies
B) Giardia and a human
C) the plant root mycorrhiza
D) the sea slug and its chloroplasts

Question 12

'Beaver fever' is caused by the Giardia duodenalis parasite that can be present in lake water. The best way to avoid beaver fever is to

A) not swim in lakes where Giardia duodenalis is present.
B) avoid eating infected beaver meat.
C) avoid drinking water from lakes where Giardia duodenalis is present.
D) avoid getting too cold while swimming.

Question 13

Liver flukes of the family Schistosomatidae will sometimes infect a human host (rather than waterfowl) where they will cause itching and discomfort, but fail to complete their life cycle. What would the host be called in this instance?

A) aberrant host
B) specialist host
C) generalist host
D) passive host

Question 14

Elephantiasis is a condition causing disfigurement in people due to excessive swelling of the extremities. The origin of the problem is tiny parasitic worms that make their home in the lymphatic system. What are these worms?

A) ectoparasites
B) endoparasites
C) parasitoids
D) endosymbionts

Question 15

The hair louse that affects humans makes its living by sucking blood from its host. What type of parasite are lice?

A) ectoparasites
B) endoparasites
C) parasitoids
D) endosymbionts

Question 16

Numerous parasites are passed from host to host by mosquito species that feed on blood. What is the term used to describe the mosquito species in this context?

A) secondary host
B) vector organism
C) tertiary host
D) parasite

Question 17

If a parasite requires two different species to complete its life cycle, what is the term used to describe its life cycle?

A) punctuated
B) direct
C) indirect
D) direct punctuated

Question 18

If a parasite infects its host under its own power, what term is given to this type of transmission?

A) passive
B) active
C) aggressive
D) direct

Question 19

In canine heartworm infections, what is the role played by mosquitoes?

A) vector
B) incubator
C) host
D) partner

Question 20

Which type of life cycle does the canine heartworm (Dirofilaria immitis) have?

A) direct
B) indirect
C) ectoparasitic
D) aberrant

Question 21

If a symbiotic relationship benefits one partner while having no discernible effect on the other partner, what is the relationship called?

A) mutualism
B) commensalism
C) parasitism
D) mimicry

Question 22

The cuckoo bird will lay its eggs in the nest of another species of bird. Upon hatching, the young cuckoo will be raised by its adoptive parents, at a cost to adoptive siblings. What type of relationship is this?

A) mutualism
B) parasitism
C) commensalism
D) mimicry

Question 23

A vampire bat can survive only a few days without a blood meal. They help each other by sharing blood, which appears to be an example of what type of behaviour?

A) commensalism
B) mutualism
C) parasitism
D) altruism

Question 24

It can be very difficult to prove the existence of altruism in a relationship between individuals. In many cases, the altruistic relationship is specific to closely related individuals. What is the term given to the relationship in this instance?

A) kin selection
B) reciprocal altruism
C) inclusive altruism
D) social altruism

Question 25

An aggressive mimic is one that

A) works particularly hard to appear to be another species.
B) has the appearance of a harmless species but is itself harmful.
C) will compete with and even fight individuals of the species it is mimicking.
D) mimics specifically the aggressive behaviour of another species.

Question 26

Which of the following definitions of mimicry is correct?

A) In Batesian mimicry, a harmless species evolves an appearance similar to a harmful species.
B) In Mullerian mimicry, a harmless species evolves an appearance similar to a harmful species.
C) In Batesian mimicry, the two species are often termed 'co-mimics.'
D) In Mullerian mimicry, three or four species are involved, and called 'multi-mimics.'

Question 27

The Ash Borer (Podosesia syringae) resembles a common species of stinging wasp, though the Ash Borer itself is incapable of stinging. In this instance, what term do we use we use to refer to the Ash Borer?

A) Mullerian mimic
B) Batesian mimic
C) Pouyannian mimic
D) aggressive mimic

Question 28

Symbioses involve the process of co-evolution of at least two species. Which is a characteristic of co-evolution?

A) ongoing evolutionary change to the genome of one species (affector), while the other species' (driver) genome does not change
B) ongoing evolutionary change in each species in response to the other species involved in the symbiotic partnership
C) periods of rapid evolutionary change punctuated by periods of stasis
D) simultaneous evolution within the genomes of an organism and an endosymbiont organelle

Question 29

Lichens are common on tree trunks and rocks throughout Canada. These composite organisms involve the symbiosis of a fungus and either a green alga or a cyanobacterium. In this symbiosis, each species is dependent upon the other. The term used to describe this type of relationship is

A) obligate symbiosis.
B) facultative symbiosis.
C) endoparasitism.
D) ectoparasitism.

Question 30

Mitochondria within human cells have their own DNA, but it is a relatively tiny genome encoding just thirteen proteins. Most of the genes required to make mitochondria are actually found in the nuclear genome of cells. What type of phenomenon is exemplified by this situation?

A) coevolution leading to degeneracy in one of the symbionts
B) genetic drift, which occurs naturally when selection pressures are relaxed
C) genetic recombination, which increases genetic variation
D) genetic selection, where the nucleus has greater fitness than mitochondria

Question 31

What is the difference between an obligate and a facultative symbiosis?

A) Obligate symbiosis occurs earlier in evolution than facultative symbiosis.
B) In an obligate symbiosis, the partners are totally dependent upon one another, which is not the case for a facultative symbiosis.
C) In an obligate symbiosis, one partner is internalized, whereas this is not the case in a facultative symbiosis.
D) A facultative symbiosis always involves degeneracy, which is not true for an obligate symbiosis.

Question 32

Symbiotic relationships should not be considered to be necessarily stable. What process continues to occur between the partners that might constantly affect and alter the nature of the relationship?

A) kin selection
B) co-evolution
C) artificial selection
D) extinction

Question 33

Many species of parasitic tapeworms that are adapted to live in the human digestive tract have lost their ability to digest food into its component macronutrients. They instead rely on the human digestive system to do this for them and simply absorb these macronutrients once they are available. The adaptation of the tapeworm in this instance is an example of

A) co-evolution.
B) adaptive radiation.
C) endoparasitism.
D) degeneracy.

Question 34

What is a cysticercoid?

A) the larval stage of a tapeworm
B) the name given to a tapeworm egg
C) the intermediate host for tapeworm parasites
D) a heart tapeworm

Question 35

The chart below provides brief definitions for five types of symbiosis discussed in this chapter. From the following options, choose which corrrectly matches each type of symbiosis with its definition.

A) A) Mutualism; B) Parasitism; C) Commensalism; D) Altruism; E) Mimicry
B) A) Mutualism; B) Commensalism; C) Parasitism; D) Altruism; E) Mimicry
C) A) Commensalism; B) Mutualism; C) Parasitism; D) Altruism; E) Mimicry
D) A) Commensalism; B) Mutualism; C) Altruism; D) Parasitism; E) Mimicry

Question 36

The two plants shown here have been watered and fertilized identically, and have been maintained in exactly the same light and temperature conditions. What is the difference between the plant on the left and the one on the right in the picture below?

A) the absence of mycorrhizal fungi in the soil on the left
B) the presence of mycorrhizal fungi in the soil on the left
C) the absence of honeybee pollinators in the soil on the left
D) the presence of honeybee pollinators in the soil on the right

Question 37

After reading the paragraph below, answer the question(s) that follow(s).
Honeybee populations in North America have been in dramatic decline over the past decade or so. The exact cause(s) are not well understood, but pesticides and mites have both been blamed. There is an urgency to solve this problem though, since honeybees play such an important role in their ecosystems. In addition to beekeepers and honey producers, many farmers are also concerned about what is going on.

-Why are bees of such importance to ecosystem health (choose the most complete answer)?

A) because honeybees have a symbiotic relationship with flowering plants
B) because honeybees have a mutualistic symbiosis with flowering plants
C) because honeybees have a diffuse mutualistic with flowering plants that involves many plant species
D) because honeybees have a diffuse parasitic relationship with flowering plants

Question 38

After reading the paragraph below, answer the question(s) that follow(s).
Honeybee populations in North America have been in dramatic decline over the past decade or so. The exact cause(s) are not well understood, but pesticides and mites have both been blamed. There is an urgency to solve this problem though, since honeybees play such an important role in their ecosystems. In addition to beekeepers and honey producers, many farmers are also concerned about what is going on.

-Which of the following represents a likely short-term outcome of the decline in honeybee populations?

A) a reduced yield of fruits from flowering plant species
B) extinction of flowering plant species
C) minimal effect because wasps and hornets will make up the difference
D) minimal effect because plants will simply self-fertilize