Question 1

A consumer,such as a bear,that eats both producers (plants)and consumers (animals)is a(n)

Accepted Answer

An omnivore is a consumer that eats both producers (plants) and consumers (animals), which fits the description of a bear.

Question 2

From the perspective of energy,which of the following is the most efficient trophic level?

Accepted Answer

The primary producer, which is the first trophic level, is the most efficient in terms of energy because it converts sunlight into organic matter through photosynthesis, retaining most of the available energy. As we move up the food chain, each successive trophic level loses a significant amount of energy in the form of heat during metabolic processes, resulting in a lower energy transfer efficiency.

Question 3

The interacting populations of living plants and animals in a particular location are described as a(n)

Accepted Answer

A community refers to a group of interacting populations of living plants and animals in a particular location. A metapopulation refers to a group of spatially separated populations of the same species that interact through migration and gene flow. An ecosystem includes both living and non-living elements of a particular environment. A niche refers to the role of a particular species in an ecosystem, while a trophic level refers to the position of a species in a food chain or food web.

Question 4

A black walnut (Juglans nigra)emits a chemical that may kill or inhibit the growth of other nearby shrubs or trees.However,the black walnut is unaffected by this interaction.This is an example of which symbiotic relationship?

Accepted Answer

The black walnut tree emits a chemical that harms other nearby plants, but it is not affected by this interaction. This is an example of amensalism, where one organism is negatively affected and the other is not affected at all.

Question 5

In coral reefs,clownfish live unharmed among the poisonous tentacles of sea anemones.The sea anemones protect the clownfish from predation,while the clownfish scare off predators,such butterfly fish,which would otherwise eat the anemones.The clownfish may also provide important nutrients to the anemones.This is an example of which symbiotic relationship?

Accepted Answer

The relationship between clownfish and sea anemones is an example of mutualism, where both species benefit from the presence of the other. The sea anemones provide protection for the clownfish, while the clownfish scare off predators and may also provide important nutrients for the anemones.

Question 6

As chemical pesticides move through the trophic pyramid,they may be amplified at each higher level in a process called

Accepted Answer

Biomagnification is the process by which chemical pollutants, such as pesticides, become increasingly concentrated in the tissues of organisms at higher trophic levels in the food chain. As a result, predators at the top of the food chain may accumulate very high levels of these pollutants, which can have harmful effects on their health and on the health of other species in the ecosystem.

Question 7

The zonation of flora and fauna along an altitudinal transect similar to that found along latitudinal transects is known as the

Accepted Answer

The term "life zone concept" refers to the zonation of flora and fauna along an altitudinal transect. This concept is similar to the latitudinal zonation of flora and fauna along a latitudinal transect.

Question 8

Currently,approximately ____of cultivated acreage in the United States and Canada is planted for animal consumption

Accepted Answer

Approximately 50% of cultivated acreage in the United States and Canada is planted for animal consumption. This reflects the significant portion of agricultural land dedicated to producing feed for livestock rather than food for direct human consumption.

Question 9

Consider a simple food chain in which a grasshopper eats grass,the grasshopper is eaten by a frog,the frog is eaten by a snake,and a burying beetle feeds on the snake after it dies.Which of the following is not correctly matched?

Accepted Answer

The snake is not a primary consumer, as it is not directly eating a producer (grass). It is a secondary consumer because it eats the frog, which is a primary consumer that eats the grasshopper (herbivore).

Question 10

Lichen are made up of algae and fungi living together.In this relationship,the alga is the producer and food source for the fungus and the fungus provides structure and physical support for the alga.This is an example of which symbiotic relationship?

Accepted Answer

Lichen have a mutualistic relationship where both the algae and fungi benefit from each other's presence, with the alga providing food for the fungus and the fungus providing structure and physical support for the alga.

Question 11

Epiphytic plants,such as various species of orchids (Orchidaceae),grow upon another plant,using the plants for physical support,but bringing no harm to the host plant.This is an example of which symbiotic relationship?

Accepted Answer

In commensalism, one organism benefits without affecting the other organism positively or negatively. In this case, the epiphytic plants benefit from the physical support provided by the host plant, but the host plant is not affected in any way.

Question 12

The proposition that no two species can occupy the same ecological niche is known as the

Accepted Answer

The proposition that no two species can occupy the same ecological niche is known as the competitive exclusion principle. This principle states that if two species are competing for the same resources in the same habitat, one species will eventually outcompete and displace the other species. This enables each species to occupy its own unique ecological niche.

Question 13

The environment in which an organism resides or is biologically adapted to live is called a(n)

Accepted Answer

Habitat refers to the specific environment in which an organism lives or is adapted to live, including both biotic (living) and abiotic (non-living) factors. Ecotone refers to the transition area between two different ecosystems or habitats. Community refers to all the different species living and interacting in a particular area. Niche refers to the specific role and interactions of a species within its community. Trophic level refers to the position of an organism in the food chain, indicating its source of energy and its role in the transfer of energy between different organisms. Therefore, habitat is the best choice for this question.

Question 14

Which of the following would not be a limiting factor for a plant species?

Accepted Answer

Soil phosphorus content, daily precipitation values, days below freezing, and water availability are all environmental factors that can limit plant growth and distribution. However, the number of predators is not typically considered a limiting factor for plant species as they are not directly affected by predation.

Question 15

In food webs,toxic chemicals tend to accumulate and concentrate most in the

Accepted Answer

Toxic chemicals, such as pesticides and heavy metals, typically biomagnify as they move up the food chain. This means that as predators eat prey, they accumulate the chemicals in their bodies. As a result, top carnivores such as apex predators are likely to have the highest concentrations of toxic chemicals in their bodies.

Question 16

The specific,unique role that a species performs within a given area is known as a(n)

Accepted Answer

The specific, unique role that a species plays within a given area is known as its niche. The niche of a species includes its interactions with other species, its habitat requirements, its food sources, and other factors that determine its place within the ecosystem. The other choices are related to the niche concept, but do not capture the specific definition of a species' role.

Question 17

Mistletoe (Phoradendron)infests many taxa of plants,often causing the branches of the host species to become swollen and distorted and making the trees more susceptible to insect infestations.This is an example of which symbiotic relationship?

Accepted Answer

Mistletoe infests and harms the host plant, making it more susceptible to other types of infestations, which is a clear example of parasitism.

Question 18

Food resources as a limiting factor for species distribution The snail kite (Rostrhamus sociabilis)is a specialist that feeds on only one specific type of snail.By comparison,the Mallard Duck (Anas platyrhynchos)is a generalist that feeds on diverse food sources.Whereas the snail kite has a very limited range,the Mallard Duck has a very broad range.The snail kite's diet is an example of a(n)

Accepted Answer

The snail kite's diet is a specific food resource that limits its distribution, making it an example of a limiting factor. The Mallard Duck, on the other hand, has a broad range due to its ability to feed on a variety of different food sources.

Question 19

____refers to the biotic and abiotic characteristics in the environment that determine species distribution.

Accepted Answer

Limiting factors are environmental conditions that limit the growth, abundance, or distribution of a species within an ecosystem.

Question 20

Only about ___ of the kilocalories in a trophic level is passed to the next trophic level (e.g. ,from autotroph to primary consumer).

Accepted Answer

On average, only about 10% of the energy in one trophic level is passed to the next level; the rest is lost largely through metabolic processes as heat.

Quiz 19: Ecosystem Essentials

A consumer,such as a bear,that eats both producers (plants) and consumers (animals) is a(n)