Ecosystems: Structure, Function, and Interactions

Question 1

In most ecosystems, which organisms are the primary producers?

Accepted Answer

Plants

Answer

Herbivores

Answer

Carnivores

Answer

Decomposers

Question 2

What is the ultimate energy source for all ecosystems on Earth?

Accepted Answer

The sun

Answer

Fossil fuels

Answer

Nuclear reactions

Answer

Geothermal energy

Question 3

What is the process by which plants convert sunlight into energy?

Accepted Answer

Photosynthesis

Answer

Respiration

Answer

Transpiration

Answer

Decomposition

Question 4

What is the significance of biodiversity in an ecosystem?

Accepted Answer

It enhances ecosystem stability and resilience.

Answer

It reduces competition among species.

Answer

It inhibits the spread of diseases.

Answer

It decreases the overall productivity of the ecosystem.

Question 5

What is the primary role of consumers in an ecosystem?

Accepted Answer

To regulate population sizes

Answer

To produce food for producers

Answer

To decompose dead organisms and recycle nutrients

Answer

To convert solar energy into chemical energy

Question 6

Which of the following is the primary source of energy for nearly all ecosystems on Earth?

Accepted Answer

Sunlight

Answer

Geothermal heat

Answer

Wind

Answer

Nuclear energy

Question 7

What is the term for a diagram that visually represents the feeding relationships between different organisms within an ecosystem?

Accepted Answer

Food web

Answer

Trophic pyramid

Answer

Energy pyramid

Answer

Nutrient cycle diagram

Question 8

Which of the following is the process by which atmospheric nitrogen is converted into a form usable by plants?

Accepted Answer

Nitrogen fixation

Answer

Nitrification

Answer

Denitrification

Answer

Assimilation

Question 9

What is the term for an ecological community of living organisms interacting with their physical environment?

Accepted Answer

Ecosystem

Answer

Biosphere

Answer

Population

Answer

Biome

Question 10

Which of the following is a biotic component of an ecosystem?

Accepted Answer

Bacteria

Answer

Sunlight

Answer

Water

Answer

Rocks

Question 11

What is the ecological term for organisms that obtain energy by consuming other organisms?

Accepted Answer

Consumers

Answer

Producers

Answer

Decomposers

Answer

Autotrophs

Question 12

What is the biological process by which plants convert light energy into chemical energy stored in glucose?

Accepted Answer

Photosynthesis

Answer

Cellular respiration

Answer

Glycolysis

Answer

Krebs cycle

Question 13

What is the process by which nutrients are released back into the ecosystem from the decomposition of organic matter?

Accepted Answer

Mineralization

Answer

Nitrification

Answer

Assimilation

Answer

Transpiration

Question 14

Which of the following is NOT a direct consequence of human activities that can contribute to the decline of coral reef ecosystems?

Accepted Answer

Hurricanes

Answer

Overfishing

Answer

Ocean acidification

Answer

Pollution

Question 15

Which statement best describes a keystone species?

Accepted Answer

A species crucial for maintaining the health and balance of its ecosystem.

Answer

A species with minimal impact on its ecosystem.

Answer

A species unaffected by other species in its ecosystem.

Answer

A species at the top of the food chain that controls all other species.

Question 16

What is the definition of ecological succession?

Accepted Answer

The gradual, predictable change in species composition of an ecological community over time.

Answer

The process of organisms adapting to their environment through natural selection.

Answer

The steady increase in biodiversity and ecosystem complexity over time.

Answer

The restoration of ecosystems after disturbances.

Question 17

Which of the following is a non-essential component of an ecosystem?

Accepted Answer

Phenology

Answer

Biotic organisms

Answer

Abiotic factors

Answer

Energy flow

Question 18

Which trophic level is responsible for initiating energy flow within an ecosystem?

Accepted Answer

Producers

Answer

Consumers

Answer

Decomposers

Answer

Apex predators

Question 19

Which sequence correctly depicts the unidirectional movement of energy within an ecosystem?

Accepted Answer

Producers → Consumers → Decomposers

Answer

Decomposers → Producers → Consumers

Answer

Consumers → Decomposers → Producers

Answer

Decomposers → Consumers → Producers

Question 20

Which process replenishes soil nutrients, making them accessible to plant life?

Accepted Answer

Composting

Answer

Nitrogen assimilation

Answer

Photosynthesis

Answer

Respiration

Question 21

In a symbiotic relationship where both parties mutually benefit, what is the appropriate term?

Accepted Answer

Mutualism

Answer

Amensalism

Answer

Commensalism

Answer

Parasitism

Question 22

Which evolutionary mechanism explains the gradual adaptation of species to their respective environments?

Accepted Answer

Natural selection

Answer

Genetic drift

Answer

Mutation

Answer

Symbiosis

Question 23

Which type of ecological succession commences after an environmental disturbance, exemplified by forest fires or volcanic eruptions?

Accepted Answer

Primary succession

Answer

Climax community

Answer

Secondary succession

Answer

Tertiary succession

Question 24

What ecological concept refers to the maximum population size an ecosystem can sustain without compromising its integrity?

Accepted Answer

Carrying capacity

Answer

Exponential growth

Answer

Immigration rate

Answer

Population density

Question 25

Which component is NOT essential for the functioning of an ecosystem?

Accepted Answer

Artificial structures

Answer

Organisms

Answer

Physical environment

Answer

Energy flow

Question 26

An example of a mutualistic relationship between two organisms is:

Accepted Answer

A bee pollinating a flower

Answer

A lion hunting a zebra

Answer

A tapeworm living in a human's intestine

Answer

A virus infecting a bacterial cell

Question 27

The carrying capacity of an ecosystem refers to:

Accepted Answer

The maximum population size that the ecosystem can sustain

Answer

The minimum amount of resources required for a population to survive

Answer

The rate at which a population grows or declines

Answer

The genetic diversity of a population

Question 28

A greenhouse gas that contributes to climate change is:

Accepted Answer

Carbon dioxide

Answer

Water vapor

Answer

Nitrogen

Answer

Oxygen

Question 29

Which component is not considered essential for the functioning of an ecosystem?

Accepted Answer

Atmosphere

Answer

Producers

Answer

Consumers

Answer

Energy

Question 30

In a food web, primary consumers primarily engage in which activity?

Accepted Answer

Consuming plants or algae

Answer

Producing their own food

Answer

Consuming other animals

Answer

Decomposing organic matter

Question 31

Which process releases carbon dioxide as a byproduct?

Accepted Answer

Cellular respiration

Answer

Photosynthesis

Answer

Nitrogen fixation

Answer

Denitrification

Question 32

What is the primary source of energy that sustains most ecosystems?

Accepted Answer

Sunlight

Answer

Wind

Answer

Geothermal heat

Answer

Chemical reactions

Question 33

Which characteristic is typically associated with a climax community?

Accepted Answer

High species diversity and stability

Answer

Low species diversity and rapid growth

Answer

Early successional stage and high disturbance

Answer

Dominated by a single species

Question 34

What is the primary function of decomposers in an ecosystem?

Accepted Answer

Breaking down dead organisms

Answer

Producing organic matter

Answer

Consuming living organisms

Answer

Fixing nitrogen from the atmosphere

Question 35

What term describes the process by which plants harness sunlight to create their own nourishment?

Accepted Answer

Photosynthesis

Answer

Chemosynthesis

Answer

Respiration

Answer

Fermentation

Question 36

Which characteristic is most commonly associated with keystone species?

Accepted Answer

Having a disproportionate impact on the ecosystem

Answer

Low population density

Answer

Occupying high trophic levels

Answer

Large physical size

Question 37

How do abiotic factors, such as climate patterns and soil composition, impact the distribution and abundance of organisms within an ecosystem?

Accepted Answer

Abiotic factors create distinct niches that organisms can inhabit.

Answer

Abiotic factors directly influence the genetic makeup of organisms.

Answer

Abiotic factors do not impact the distribution and abundance of organisms.

Answer

Abiotic factors solely affect the behavior, not the distribution or abundance, of organisms.

Question 38

Explain the key differences between autotrophs and heterotrophs, and how these differences impact their ecological roles within ecosystems.

Accepted Answer

Autotrophs produce their own food from inorganic molecules, while heterotrophs consume other organisms for energy.

Accepted Answer

Autotrophs are responsible for primary production, while heterotrophs transfer energy through higher trophic levels.

Accepted Answer

Autotrophs have chloroplasts for photosynthesis, which heterotrophs lack.

Answer

Autotrophs typically have greater biomass and diversity than heterotrophs in ecosystems.

Question 39

Which of the following is NOT considered a component of an ecosystem?

Accepted Answer

Cultural practices

Answer

Biotic factors (living organisms)

Answer

Abiotic factors (non-living factors)

Answer

Energy flow

Question 40

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

Accepted Answer

Energy flow

Answer

Photosynthesis

Answer

Respiration

Answer

Decomposition

Question 41

In most ecosystems, which organisms are the primary producers?

Accepted Answer

Plants

Answer

Herbivores

Answer

Carnivores

Answer

Decomposers

Question 42

Which of the following is NOT a potential factor influencing the dynamics of an ecosystem?

Accepted Answer

Lunar phases

Answer

Climate change

Answer

Introduction of invasive species

Answer

Human activities

Question 43

The concept of a limiting factor implies that:

Accepted Answer

A single resource can restrict the growth and survival of an organism

Answer

All resources are equally essential for an organism's survival

Answer

Resources are always abundant in nature

Answer

Competition plays no role in ecosystems

Question 44

The process of breaking down organic matter by microorganisms is referred to as:

Accepted Answer

Decomposition

Answer

Respiration

Answer

Photosynthesis

Answer

Combustion

Question 45

The concept of ecosystem services highlights that:

Accepted Answer

Ecosystems offer valuable benefits to humans

Answer

Ecosystems are only beneficial to wildlife

Answer

Humans are the sole beneficiaries of ecosystems

Answer

Ecosystems are unaffected by human activities

Question 46

Which of the following is NOT a fundamental component of an ecosystem?

Accepted Answer

Atmosphere

Answer

Living organisms (biotic factors)

Answer

Non-living components (abiotic factors)

Answer

Energy

Question 47

In a food web, which type of organism typically forms the base of the food chain?

Accepted Answer

Producers

Answer

Scavengers

Answer

Consumers

Answer

Predators

Question 48

Which biological process directly converts carbon dioxide into organic compounds?

Accepted Answer

Photosynthesis

Answer

Respiration

Answer

Decomposition

Question 49

Nutrient cycling within an ecosystem involves:

Accepted Answer

A continuous exchange of nutrients between living organisms and the environment.

Answer

Exclusively relying on decomposers for nutrient breakdown.

Answer

Occurring solely through the process of photosynthesis.

Question 50

Which of the following factors directly influences the carrying capacity of an ecosystem?

Accepted Answer

Food availability

Answer

Air pressure

Answer

Moon phase

Answer

Distance to the nearest river

Question 51

Ecological succession refers to the:

Accepted Answer

Gradual and predictable change in the species composition of a community over time.

Answer

Random fluctuation in population sizes.

Answer

Permanent shift in environmental conditions.

Question 52

Which of the following is a classic example of a keystone species?

Accepted Answer

Sea otter

Answer

Plankton

Answer

Earthworm

Answer

Lion

Question 53

The process by which organisms adapt to their environment through natural selection is known as:

Accepted Answer

Evolution

Answer

Adaptation

Answer

Speciation

Answer

Mutation

Question 54

Which of the following human activities has a significant and often negative impact on ecosystems?

Accepted Answer

Deforestation

Answer

Birdwatching

Answer

Cloudwatching

Answer

Hiking

Question 55

The scientific study of the interactions between organisms and their environment is called:

Accepted Answer

Ecology

Answer

Chemistry

Answer

Physics

Answer

Biology