Ecology Quizzes: Test Your Knowledge of Ecosystems and the Environment

Question 1

Which characteristic is NOT associated with a climax community?

Accepted Answer

Pioneering species dominate

Answer

Stable species composition

Answer

High biodiversity

Answer

Low net productivity

Question 2

In a food chain, which trophic level is immediately below a tertiary consumer?

Accepted Answer

Secondary consumer

Answer

Producer

Answer

Primary consumer

Answer

Decomposer

Question 3

Which density-dependent factor is most likely to limit the growth of a rapidly increasing rabbit population?

Accepted Answer

Competition for resources

Answer

Predation

Answer

Disease

Answer

Natural disasters

Question 4

Which of the following biomes is characterized by frigid temperatures, extended winters, and evergreen coniferous trees?

Accepted Answer

Taiga

Answer

Tropical rainforest

Answer

Temperate deciduous forest

Answer

Tundra

Question 5

What is the ecological role of a keystone species?

Accepted Answer

Maintaining ecosystem stability

Answer

Reducing competition among species

Answer

Providing food for top predators

Answer

Increasing biodiversity

Question 6

Which process recycles nutrients within an ecosystem?

Accepted Answer

Decomposition

Answer

Photosynthesis

Answer

Respiration

Answer

Transpiration

Question 7

Identify the characteristic that best describes a healthy ecosystem:

Accepted Answer

High levels of biodiversity and stable nutrient cycling

Answer

Low levels of pollution and minimal human interference

Answer

Abundance of all species, regardless of their ecological roles

Answer

Absence of natural disturbances and a predictable environment

Question 8

In an ecosystem, decomposers play a crucial role. Which of the following accurately describes their function?

Accepted Answer

They convert dead organisms into simpler substances, making nutrients available for other organisms.

Answer

They produce organic matter by capturing energy from the sun.

Answer

They consume plants and animals, regulating their populations.

Answer

They fix nitrogen from the atmosphere, providing it to other organisms.

Question 9

Which factors collectively influence the growth rate of a population?

Accepted Answer

Birth and death rates, as well as immigration and emigration

Answer

Availability of resources and the presence of predators

Answer

Climate conditions and the size of the population

Answer

Competition for mates and the rate of genetic mutation

Question 10

Distinguish between a keystone species and a dominant species. Which statement accurately describes their respective ecological roles?

Accepted Answer

Keystone species disproportionately influence the ecosystem relative to their abundance, while dominant species are simply the most numerous.

Answer

Keystone species are always predators, whereas dominant species are always herbivores.

Answer

Dominant species have a negative impact on the ecosystem, while keystone species have a positive impact.

Answer

Keystone species and dominant species have identical ecological roles.

Question 11

Which biome is characterized by cold temperatures, frozen ground, and limited precipitation?

Accepted Answer

Tundra with low temperatures and sparse vegetation

Answer

Temperate forest with lush vegetation and abundant rainfall

Answer

Tropical rainforest with high humidity and diverse plant life

Answer

Grassland with vast open areas and grazing herbivores

Question 12

Which of the following poses a significant threat to global biodiversity?

Accepted Answer

All of the above pose threats to biodiversity

Answer

Habitat destruction due to human activities, such as deforestation

Answer

Pollution from industrial processes and vehicle emissions

Answer

Invasive species introduced to new environments

Question 13

Which of the following is an example of a natural disturbance that can impact ecosystems?

Accepted Answer

All of the above are examples of natural disturbances

Answer

Wildfires that can clear vegetation and create new habitats

Answer

Droughts that can stress organisms and alter ecosystem composition

Answer

Hurricanes that can cause widespread damage and reshape landscapes

Question 14

Define carrying capacity and explain its relevance to population ecology.

Accepted Answer

The maximum sustainable population size that an environment can support, influencing population growth and resource availability

Answer

The average lifespan of individuals within a population, affecting population dynamics

Answer

The rate at which a population increases or decreases, impacted by various factors

Answer

The number of predators in a specific ecosystem, regulating prey populations

Question 15

How do decomposers contribute to an ecosystem? Explain their role in nutrient cycling.

Accepted Answer

Decomposers break down organic matter, releasing nutrients back into the ecosystem for plants to use.

Answer

Decomposers are a primary food source for animals higher up the food chain.

Answer

Decomposers help control the population of herbivores by consuming excess plant matter.

Answer

Decomposers have a minor impact on the overall health of an ecosystem.

Question 16

In a food chain, the organisms that cannot produce their own food and must consume other organisms are called:

Accepted Answer

Consumers

Answer

Producers

Answer

Decomposers

Answer

Predators

Question 17

Which type of population growth occurs when the population size increases rapidly at first and then slows down as it reaches the carrying capacity?

Accepted Answer

Logistic growth

Answer

Exponential growth

Answer

Zero growth

Answer

Negative growth

Question 18

The gradual and predictable change in plant and animal communities over time is known as:

Accepted Answer

Succession

Answer

Competition

Answer

Biodiversity

Answer

Ecosystem dynamics

Question 19

The limit to the number of individuals that an environment can support is referred to as:

Accepted Answer

Carrying capacity

Answer

Population density

Answer

Birth rate

Answer

Death rate

Question 20

Which type of symbiotic relationship benefits both species involved?

Accepted Answer

Mutualism

Answer

Commensalism

Answer

Parasitism

Answer

Predation

Question 21

The branch of science that studies the relationship between living organisms and their physical environment is:

Accepted Answer

Ecology

Answer

Biology

Answer

Chemistry

Answer

Physics

Question 22

The process by which organisms adapt to their environment through variations in their inherited traits is known as:

Accepted Answer

Natural selection

Answer

Genetic engineering

Answer

Phenotypic plasticity

Answer

Symbiosis

Question 23

The conversion of nitrogen into a form usable by plants is known as:

Accepted Answer

Nitrogen fixation

Answer

Denitrification

Answer

Ammonification

Answer

Nitrification

Question 24

Which of the following organisms is a primary producer in an ecosystem?

Accepted Answer

Grass

Answer

Deer

Answer

Fungi

Answer

Bacteria

Question 25

The theory that Earth's temperature is regulated by atmospheric greenhouse gases is known as:

Accepted Answer

The greenhouse effect

Answer

The Gaia hypothesis

Answer

The theory of relativity

Answer

Quantum theory

Question 26

Carrying capacity refers to the:

Accepted Answer

Maximum population size an environment can sustainably support

Answer

Rate of population growth

Answer

Genetic diversity of a population

Answer

Amount of food available in an ecosystem

Question 27

The process by which organisms use sunlight to convert inorganic matter into organic molecules is known as:

Accepted Answer

Photosynthesis

Answer

Respiration

Answer

Chemosynthesis

Answer

Fermentation

Question 28

A group of deer living in a specific area forms a:

Accepted Answer

Population

Answer

Community

Answer

Biome

Answer

Ecosystem

Question 29

The process by which dead organisms are broken down and nutrients are released back into the environment is known as:

Accepted Answer

Decomposition

Answer

Nitrification

Answer

Denitrification

Answer

Photosynthesis

Question 30

Which biome is characterized by low temperatures, frozen soil, and sparse vegetation?

Accepted Answer

Tundra

Answer

Temperate forest

Answer

Tropical rainforest

Answer

Grassland

Question 31

The principle of limiting factors implies that:

Accepted Answer

Resource availability determines organism abundance

Answer

All resources have equal limiting effects

Answer

The most scarce resource always limits population growth

Answer

Population growth is consistently exponential

Question 32

In an ecosystem, which organism is primarily responsible for producing organic matter from inorganic sources?

Accepted Answer

Plants use sunlight, carbon dioxide, and water to create glucose.

Answer

Herbivores consume plants and other herbivores.

Answer

Carnivores consume herbivores and other carnivores.

Answer

Decomposers break down dead organisms.

Question 33

A population of deer experiences a sharp decline due to a disease outbreak. Which of the following is the most likely impact on the ecosystem?

Accepted Answer

Increased plant growth due to reduced grazing pressure from deer.

Answer

Increased competition for food among predators that prey on deer.

Answer

No significant impact on the ecosystem.

Answer

A rapid increase in the deer population due to reduced predation.

Question 34

Which of the following is NOT a defining characteristic of a keystone species?

Accepted Answer

It is found in all ecosystems.

Answer

It exerts a disproportionate impact on the community relative to its abundance.

Answer

It is often a predator or herbivore.

Answer

Its removal can cause a cascade effect in the community.

Question 35

The concept of ecological succession suggests that:

Accepted Answer

Ecological communities change over time.

Answer

Competition among species decreases as succession progresses.

Answer

Biodiversity decreases as succession progresses.

Answer

Abiotic factors play no role in succession.

Question 36

The scientific study of interactions between organisms and their environment is known as:

Accepted Answer

Ecology

Answer

Biology

Answer

Zoology

Answer

Environmental Science

Question 37

Which of the following biomes is characterized by frigid temperatures, low precipitation, and limited vegetation?

Accepted Answer

Tundra

Answer

Temperate forest

Answer

Tropical rainforest

Answer

Grassland

Question 38

The scientific discipline that explores interactions between organisms and their physical surroundings is:

Accepted Answer

Ecology

Answer

Environmental science

Answer

Ecosystem dynamics

Answer

Population biology

Question 39

In an ecosystem, the organisms responsible for initiating the energy flow are the:

Accepted Answer

Producers

Answer

Consumers

Answer

Decomposers

Answer

Top predators

Question 40

The process by which energy moves through an ecosystem is known as:

Accepted Answer

Energy cycling

Answer

Nutrient cycling

Answer

Water cycling

Answer

Biogeochemical cycling

Question 41

The theory of evolution by natural selection was primarily developed by:

Accepted Answer

Charles Darwin

Answer

Gregor Mendel

Answer

James Watson and Francis Crick

Answer

Louis Pasteur

Question 42

Which characteristic is NOT typical of a healthy ecosystem?

Accepted Answer

Absence of competition between species

Answer

High biodiversity

Answer

Efficient nutrient cycling

Answer

Ability to withstand environmental disturbances

Question 43

In an ecosystem, the transfer of energy from one organism to another is known as:

Accepted Answer

Food chain

Answer

Photosynthesis

Answer

Cellular respiration

Answer

Biodiversity

Question 44

The maximum number of individuals of a species that an environment can sustain is called:

Accepted Answer

Carrying capacity

Answer

Available resources

Answer

Competition

Answer

Predation

Question 45

Ecological succession refers to:

Accepted Answer

The gradual change in a community over time

Answer

The arrival of new species into a new area

Answer

The formation of new ecosystems

Answer

The effects of human activity on the environment

Question 46

The process by which nitrogen from the atmosphere is converted into a form usable by plants is called:

Accepted Answer

Nitrogen fixation

Answer

Nitrification

Answer

Denitrification

Answer

Assimilation

Question 47

Which type of ecological interaction involves two organisms benefitting from each other?

Accepted Answer

Symbiosis

Answer

Predation

Answer

Parasitism

Answer

Competition

Question 48

What term describes the transfer of energy from one level of an ecosystem to the next in a food chain?

Accepted Answer

Trophic transfer

Answer

Primary production

Answer

Secondary production

Answer

Ecological efficiency

Question 49

What is the ecological community that would naturally develop in a specific region if there was no human interference?

Accepted Answer

Climax community

Answer

Pioneer community

Answer

Secondary community

Answer

Seral community

Question 50

Which process enables plants to convert sunlight into usable energy?

Accepted Answer

Photosynthesis

Answer

Respiration

Answer

Chemosynthesis

Answer

Aerobic respiration

Question 51

How is biodiversity linked to the stability of an ecosystem?

Accepted Answer

A positive correlation exists

Answer

A negative correlation exists

Answer

There is no correlation

Answer

The relationship varies depending on the ecosystem

Question 52

Which species plays a disproportionately large role in its ecosystem relative to its abundance?

Accepted Answer

Sea otter

Answer

White-tailed deer

Answer

African elephant

Answer

Red fox

Question 53

Differentiate between a habitat and a niche.

Accepted Answer

A habitat refers to the physical location where an organism lives, while a niche describes its functional role in the ecosystem.

Answer

A niche refers to the physical location where an organism lives, while a habitat describes its functional role in the ecosystem.

Answer

Habitat and niche are interchangeable terms.

Answer

There is no distinction between habitat and niche.

Question 54

Which of the following interactions involves a close relationship where both species benefit?

Accepted Answer

Mutualism

Answer

Predation

Answer

Parasitism

Answer

Symbiosis

Question 55

The maximum number of individuals of a species that an environment can support indefinitely is known as its:

Accepted Answer

Carrying capacity

Answer

Population size

Answer

Growth rate

Answer

Density

Question 56

Biodiversity encompasses all of the following EXCEPT:

Accepted Answer

Number of populations

Answer

Variety of species

Answer

Abundance of species

Answer

Ecosystem function

Question 57

Which of the following biomes is characterized by low temperatures, high rainfall, and coniferous vegetation?

Accepted Answer

Tundra

Answer

Desert

Answer

Tropical rainforest

Answer

Grassland

Question 58

The process by which plants utilize sunlight to produce chemical energy is called:

Accepted Answer

Photosynthesis

Answer

Respiration

Answer

Chemosynthesis

Answer

Glycolysis

Question 59

What is the gradual change in the makeup of species in a community over time called?

Accepted Answer

Ecological succession

Answer

Population growth

Answer

Competition

Answer

Predation

Question 60

Which of the following describes a climax community?

Accepted Answer

High biodiversity and low species turnover

Answer

Dominated by early successional species and rapid growth

Answer

Low species diversity and high rates of species turnover

Answer

High species turnover and rapid growth

Question 61

What is the role of decomposers in an ecosystem?

Accepted Answer

Break down dead organisms, releasing nutrients into the soil

Answer

Produce food for primary consumers

Answer

Control populations of herbivores

Answer

Prevent the spread of disease

Question 62

Which of the following represents a population?

Accepted Answer

A group of organisms of the same species living in a defined area

Answer

An individual organism

Answer

All organisms living in a specific habitat

Answer

A collection of species that interact with each other

Question 63

The process by which plants utilize sunlight to produce energy is known as:

Accepted Answer

Photosynthesis

Answer

Respiration

Answer

Chemosynthesis

Answer

Fermentation

Question 64

Mutualism is a type of symbiotic relationship where:

Accepted Answer

Both species benefit from the interaction

Answer

One species benefits while the other is unaffected

Answer

One species benefits at the expense of the other

Answer

Neither species is affected by the interaction