Question 1

Human cells contain mitochondria,which are responsible for processing the energy needed by our cells.Remember that the ancestors of mitochondria may once have been free-living prokaryotes.If mitochondria were still considered separate organisms within human cells,which of the following would best describe the relationship with them?
A) parasitic
B) mutualistic
C) competitive
D) pathogenic

Accepted Answer

The relationship between human cells and mitochondria can be described as mutualistic because mitochondria provide energy for the cells and, in return, the cells provide a protected and stable environment for mitochondria to survive and reproduce. While mitochondria were once independent organisms, they have evolved to exist in a mutually beneficial relationship with their host cells. Parasitic, competitive, and pathogenic relationships do not accurately describe the relationship between human cells and mitochondria.

Question 2

As the following figure illustrates,communities vary tremendously in size from as large as an entire forest to the digestive system of a single deer.  How do biologists recognize communities?
A) Large communities are often defined by the distribution of their members, but small communities are often simply defined according to what is convenient at a given point in time.
B) Communities can be nested within a larger one; for example, the deer is part of the woodland, which is part of the forest.
C) Communities are recognized by the minimal species composition criterion: all communities must have eight or more species.
D) Communities have dynamic characteristics similar to those of populations; they consist of the habitat and species critical to the community growth rate.

Accepted Answer

A

Question 3

Which of the following best illustrates behavioral mutualism?
A) Fruit seeds pass through a consumer's digestive system and are moved to a location distant from the parent plant.
B) Pollen from one plant is carried to another.
C) Small fish called cleaner wrasse remove parasites from the mouth and gills of predatory fish.
D) Infected individuals experience diarrhea that releases infectious organisms into the environment.

Accepted Answer

Behavioral mutualism involves two or more species cooperating in a way that benefits both. Cleaner wrasses remove parasites from the mouths and gills of predatory fish, providing a valuable service to the larger fish while getting a meal out of the deal. This is an example of behavioral mutualism. The other choices do not involve mutualism, as they either involve one species benefiting at the expense of another (option A and D) or a natural process of pollination (option B).

Question 4

If researchers were to document that the diversity of anemones lacking resident clownfish was approximately equal to those with clownfish,it would suggest that the interaction between these two species was
A) behavioral mutualism.
B) symbiotic.
C) commensalistic.
D) exploitative.

Accepted Answer

The answer of If researchers were to document that the...

Question 5

Which of the following combinations of symbols represents an interaction in which one species benefits and the other is exploited?
A) +/-
B) +/+
C) o/+
D) -/-

Accepted Answer

The combination of symbols "+" and "-" represents a type of relationship between species known as "predation" or "parasitism". In this interaction, one species benefits (+) by feeding on or using the resources of the other species, which is harmed (-) by the interaction. Therefore, option A (+/-) is the best choice as it represents an interaction in which one species benefits and the other is exploited.

Question 6

Do humans exhibit any mutualistic relationships?
A) No; humans can only develop parasitic relationships with other organisms.
B) Yes; humans host disease pathogens that limit population growth and overcrowding.
C) Yes; in the absence of technology, humans quickly become prey for other predators.
D) Yes; humans host beneficial bacteria within our digestive systems.

Accepted Answer

Humans exhibit a mutualistic relationship with beneficial bacteria within our digestive systems. These bacteria help to break down food and extract nutrients for us, while in return they have a stable environment and a source of nutrients.

Question 7

Clownfish have evolved to live safely between the stinging tentacles of certain sea anemones.The fish receives protection from predators,whereas the anemone receives some food from the fish.This relationship is an example of
A) nutritional mutualism.
B) consumer interaction.
C) competitive limitation.
D) behavioral mutualism.

Accepted Answer

The relationship between clownfish and sea anemones is an example of behavioral mutualism because the fish receive protection, whereas the anemone receives food from the fish. The behavior of the clownfish (living in the anemone's tentacles) benefits both species.

Question 8

Every healthy human digestive system is home to countless microorganisms.In a normal digestive system,what type of relationship would you say this is?
A) parasitic
B) mutualistic
C) competitive
D) pathological

Accepted Answer

In a normal digestive system, the relationship between the host and the microorganisms is mutualistic, where both the host and the microorganisms benefit from each other. The microorganisms aid in digestion and nutrient absorption, while the host provides them with a steady source of nutrients and a suitable environment to live in.

Question 9

Antibiotic therapy sometimes reduces the population of gut-inhabiting microorganisms.Bloating and diarrhea often follow until the populations reestablish themselves.This observation suggests that these microorganisms participate in a(n)________ relationship with humans.
A) competitive
B) exploitative
C) mutualistic
D) pathogenic

Accepted Answer

The fact that the reduction of gut microorganisms leads to adverse effects like bloating and diarrhea, suggests that these microorganisms are likely involved in a mutualistic relationship with humans, in which both parties benefit from the association. In other words, the gut microorganisms provide benefits to the human host, such as aiding in digestion, producing vitamins, and preventing pathogenic bacteria from colonizing the gut.

Question 10

In seed-dispersal mutualism,plants produce ________ to entice consumers to disperse the plant's seeds.
A) attractive aromas
B) fleshy fruits
C) edible pollen
D) nectar

Accepted Answer

Plants use fleshy fruits to entice animals to eat them and disperse their seeds. The animals benefit by getting a tasty and nutritious meal, while the plant benefits by having its seeds transported to new locations. Attractive aromas, edible pollen, and nectar are also used by plants to attract pollinators, but not necessarily seed dispersers.

Question 11

An animal eats fruit from a plant and later deposits seed in its feces far from the plant.This is an example of a
A) pollinator mutualism.
B) gut inhabitant mutualism.
C) behavioral mutualism.
D) seed dispersal mutualism.

Accepted Answer

This scenario describes seed dispersal mutualism, where an animal unknowingly helps a plant disperse its seeds by eating the fruit and then depositing the seeds far away from the parent plant through its feces. This mutualism benefits both the plant and animal, as the animal gets nutrition from the fruit while the plant has a better chance of spreading its seeds and reproducing in a new area.

Question 12

Some algae and fungi live in associations known as lichens,which allow both to survive in a harsher environment than either could normally live in alone.This association is an example of
A) parasitism.
B) mutualism.
C) consumerism.
D) competition.

Accepted Answer

The relationship between algae and fungi in lichens is an example of mutualism, where both organisms benefit from the association. The algae provide nutrients through photosynthesis, while the fungi provide a protective environment for the algae to live in. This allows them to survive in harsh environments where neither organism could live alone.

Question 13

In comparing Communities A and B below,the major difference between them is that they differ in 
A) species richness.
B) relative species abundance.
C) that Community A has more primary producers than does Community B.
D) that Community B has more primary producers than does Community A.

Accepted Answer

The answer of In comparing Communities A and B below,the...

Question 14

Which of the following animals would be most likely to simultaneously participate in seed dispersal and a gut inhabitant mutualism?
A) wolves
B) rattlesnakes
C) scorpions
D) deer

Accepted Answer

Deer are known to participate in seed dispersal through their consumption of fruits and berries, which then pass through their digestive tract and are deposited elsewhere. They also serve as hosts for gut inhabitant mutualisms, such as the bacteria that help break down plant material in their digestive system. Wolves, rattlesnakes, and scorpions are not known for participating in seed dispersal or having gut inhabitant mutualisms.

Question 15

Can a human being be considered an ecological community?
A) Yes; for example, a community of microorganisms lives within the human digestive system.
B) Yes; human beings live with other humans, own pets, and grow domesticated crops.
C) No; a community is formed from many populations, and it takes more than one individual to make up a population.
D) No; human populations are artificial rather than natural and are considered to fall outside of ecology.

Accepted Answer

Human beings can be considered an ecological community because they host many microorganisms within their digestive system, which form a community. This community interacts with the human host, and both parties benefit from this relationship.

Answer: B
 Human beings can also be considered an ecological community because they live in close proximity to other humans, own pets, and grow domesticated crops. All of these factors contribute to the formation of an ecological community because they interact with each other and their environment.

Answer: C and D are incorrect because C defines a population, not a community, and D is not accurate because human populations are a part of ecology and can be studied using ecological principles.

Question 16

In the pollinator mutualism between the yucca plant and the yucca moth,the yucca plant is able to abort the seeds in any given flower if the moth lays too many eggs in that flower.What is the advantage the yucca plant gains by aborting these seeds?
A) The yucca plant is responsible for keeping the yucca moth population at a reasonable size.
B) Seeds are energetically expensive to produce, and if the moth larvae are going to eat most of the seeds in one fruit, the plant is able to save energy by aborting those seeds.
C) The carrying capacity of the yucca moth is increased every time it lays an egg in a yucca plant's flower, so the fewer seeds that are produced by the plant, the higher the carrying capacity of the moth can be.
D) The carrying capacity of the yucca moth is reduced every time it lays an egg in a yucca plant's flower, so the fewer seeds that are produced by the plant, the higher the carrying capacity of the moth can be.

Accepted Answer

Seeds are energetically expensive to produce, and if the moth larvae are going to eat most of the seeds in one fruit, the plant is able to save energy by aborting those seeds. By aborting some of the seeds, the yucca plant can ensure that the remaining seeds have a higher chance of surviving and being dispersed by the yucca moth to other plants, increasing the chance of successful reproduction.

Question 17

Relationships between different species often involve energy or lifestyle compromises.What best describes the compromises,if any,seen in mutualism?
A) no compromises to either organism
B) fatal to at least one of the organisms
C) a compromise (for example, dietary restriction) to one organism but not the other
D) slight compromises (for example, habitat restriction) to both organisms

Accepted Answer

In mutualism, both species benefit from the relationship, but there are often slight compromises, such as habitat or resource sharing, that both organisms must make to maintain the mutualistic relationship.

Question 18

Which of the following patterns represents the outcomes of a mutualistic relationship?
A) +/-
B) +/+
C) o/+
D) -/-

Accepted Answer

A mutualistic relationship is a type of symbiotic relationship where both species involved benefit from the interaction. The "+/+" symbol represents a mutually beneficial relationship, with both species having a positive effect on each other.

Question 19

The relationship between house pets and people would be best described as
A) parasitic.
B) mutualistic.
C) predatorial.
D) competitive.

Accepted Answer

The relationship between house pets and people is mutualistic, meaning both parties benefit from the relationship. People provide food, shelter, and care for their pets, while pets provide companionship, love, and potential health benefits for their owners.

Question 20

Which of the following statements about communities is true?
A) They usually have few species of organisms.
B) There can be complex interactions between the organisms that make up a community.
C) They are more abundant in temperate areas.
D) They are made up of mammal species only.

Accepted Answer

Communities can have many different species of organisms and the interactions between these organisms can be complex and diverse, such as predation, competition, and mutualism. The abundance of communities is not necessarily tied to temperate areas and they can include a variety of animal groups, not just mammals.

Quiz 23: Ecological Communities

As the following figure illustrates,communities vary tremendously in size from as large as an entire forest to the digestive system of a single deer. How do biologists recognize communities?

Which of the following best illustrates behavioral mutualism?

If researchers were to document that the diversity of anemones lacking resident clownfish was approximately equal to those with clownfish,it would suggest that the interaction between these two species was

Which of the following combinations of symbols represents an interaction in which one species benefits and the other is exploited?

Do humans exhibit any mutualistic relationships?

Clownfish have evolved to live safely between the stinging tentacles of certain sea anemones.The fish receives protection from predators,whereas the anemone receives some food from the fish.This relationship is an example of

Every healthy human digestive system is home to countless microorganisms.In a normal digestive system,what type of relationship would you say this is?

Antibiotic therapy sometimes reduces the population of gut-inhabiting microorganisms.Bloating and diarrhea often follow until the populations reestablish themselves.This observation suggests that these microorganisms participate in a(n) ________ relationship with humans.

In seed-dispersal mutualism,plants produce ________ to entice consumers to disperse the plant's seeds.

An animal eats fruit from a plant and later deposits seed in its feces far from the plant.This is an example of a

Some algae and fungi live in associations known as lichens,which allow both to survive in a harsher environment than either could normally live in alone.This association is an example of

In comparing Communities A and B below,the major difference between them is that they differ in

Which of the following animals would be most likely to simultaneously participate in seed dispersal and a gut inhabitant mutualism?

Can a human being be considered an ecological community?

In the pollinator mutualism between the yucca plant and the yucca moth,the yucca plant is able to abort the seeds in any given flower if the moth lays too many eggs in that flower.What is the advantage the yucca plant gains by aborting these seeds?

Relationships between different species often involve energy or lifestyle compromises.What best describes the compromises,if any,seen in mutualism?

Which of the following patterns represents the outcomes of a mutualistic relationship?

The relationship between house pets and people would be best described as

Which of the following statements about communities is true?