Question 1

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

Mutualism is the symbiotic relationship where both organisms benefit from the partnership. In this case, both the alga and the fungus benefit from each other, making it a mutualistic relationship.

Question 2

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

Accepted Answer

Soil phosphorus content, daily precipitation values, and days below freezing are all abiotic factors that can limit plant growth and survival. However, the number of predators is a biotic factor that could negatively impact plants indirectly by preying on herbivores that feed on the plants. Therefore, C is the correct answer as it is the only biotic factor listed.

Question 3

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

Accepted Answer

Only about 10% of the energy from one trophic level is passed on to the next trophic level. This is known as the 10% law, which states that only 10% of the energy is transferred from one level to the next due to energy lost through respiration, feces, and heat. The remaining 90% is lost as heat or used by the organism at that level of the food chain. This means that each successive trophic level has less energy available to it, which is why food chains tend to be relatively short.

Question 4

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 as 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

This is an example of mutualism, where both the clownfish and sea anemones benefit from their relationship.

Question 5

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

Accepted Answer

The life zone concept refers to the zonation of flora and fauna along an altitudinal transect, which is similar to that found along latitudinal transects. This concept was first proposed by C. Hart Merriam in 1894, and it divides mountainous regions into different life zones based on their elevation and climate. The life zones range from the desert zone at lower elevations to the alpine zone at higher elevations, each with characteristic vegetation and animal species.

Question 6

Which is the environment in which an organism resides or is biologically adapted to live?

Accepted Answer

Habitat is the environment in which an organism resides or is biologically adapted to live.

A) Ecotone refers to the transition area between two biomes where they meet and blend.

C) Community refers to all the populations of different species that live and interact in a particular place.

D) Niche refers to the role and position of a species within its ecosystem, including how it obtains its resources and interacts with other organisms.

Question 7

Which 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, encompassing both biotic and abiotic characteristics.

Question 8

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

This is an example of commensalism, as the epiphytic plant benefits by using the host plant for physical support, but the host plant is not harmed and neither benefits nor is harmed.

Question 9

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 which of the following?

Accepted Answer

The answer of  The snail kite (Rostrhamus sociabilis)is a...

Question 10

A consumer,such as a bear,that eats both producers (plants)and consumers (animals)is which of the following?

Accepted Answer

An omnivore is an organism that feeds on both plants and animals. Since the bear eats both plants and animals, it is considered an omnivore.

Question 11

Which are the interacting populations of living plants and animals in a particular location?

Accepted Answer

A community is defined as the 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 at some level. An ecosystem is a community of living organisms in conjunction with the nonliving components of their environment, interacting as a system. A niche refers to the role or function of an organism or population within an ecological community.

Question 12

Consider a simple food chain in which a grasshopper eats grass,the grasshopper is eaten by a frog,and the frog is eaten by a snake.Which of the following is correctly matched?

Accepted Answer

A herbivore is an animal that eats only plants, and a grasshopper eats grass. Therefore, the correct match is Grasshopper-herbivore. The grass is the primary producer, the grasshopper is the primary consumer (as it eats the grass), the frog is the secondary consumer (as it eats the grasshopper), and the snake is the tertiary consumer (as it eats the frog).

Question 13

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

This is an example of amensalism, where one species (the black walnut) is unaffected by its release of a chemical that harms other nearby species.

Question 14

Mistletoe (Phoradendron)infest 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 vulnerable to other threats. This is a classic example of parasitism.

Question 15

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

Accepted Answer

Primary producers are the most efficient trophic level because they convert the energy from the sun into organic matter through photosynthesis. This process captures the maximum amount of available energy from the sun and makes it available for higher trophic levels. As energy is lost at each trophic level through respiration, heat production, and waste discharge, the efficiency of energy transfer decreases. Therefore, primary producers are the most efficient trophic level.

Question 16

As chemical pesticides move through the trophic pyramid,they may be amplified at each higher level.Which is this process?

Accepted Answer

Biomagnification is the process by which chemical pesticides or other pollutants become increasingly concentrated in the bodies of organisms at each higher trophic level in the food chain. This is due to the fact that a predator at a higher trophic level consumes many prey items that have accumulated the pollutant in their tissues, leading to a buildup of the pollutant in the predator's body. This can result in toxic effects on the predator, other organisms in the food chain, and even on human health if the predator is consumed by humans.

Question 17

In food webs,toxic chemicals tend to accumulate and concentrate most in which level?

Accepted Answer

Toxic chemicals, also known as bioaccumulative substances, tend to accumulate and become more concentrated as they move up the food chain. This is because each level of the food chain consumes organisms from the level below, resulting in an accumulation of toxins in the tissues of the top predators, such as apex predators like eagles and polar bears. These top predators have a higher concentration of toxins than lower level organisms, which makes them more vulnerable to health problems and population decline. Therefore, the highest level of the food chain, which is usually occupied by top carnivores, tends to have the highest accumulation of toxic chemicals.

Question 18

Which is the specific,unique role that a species performs within a given area?

Accepted Answer

A niche refers to the specific, unique role that a species performs within a given area, including its interactions with other species, its use of resources, and its effect on the environment. The other options are not the best choice because they refer to broader concepts in ecology: ecotone refers to a transition zone between two different ecosystems, habitat refers to the physical and biological environment where an organism lives, and community refers to the assemblage of different species living in a particular area.

Question 19

Currently,approximately which percentage of cultivated acreage in Canada and the United States is planted for animal consumption?

Accepted Answer

According to the United Nations Food and Agriculture Organization, roughly half of the cultivated land in Canada and the United States is used for animal feed or forage. This includes grazing land, as well as crops such as corn and soybeans that are commonly used for livestock feed.

Question 20

Which is the proposition that no two species can occupy the same ecological niche?

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 two species competing for the same limited resources cannot coexist indefinitely and one species will eventually outcompete and exclude the other.

Quiz 19: Ecosystem Essentials