Ecosystems: The Living World - Biology Sixth Form Quizzes

Question 1

Which statement about food webs is FALSE?

Accepted Answer

Every organism in a food web belongs to the same trophic level.

Answer

Food webs show the feeding connections between different species in an ecosystem.

Answer

Food webs are essential for ecosystem stability and nutrient cycling.

Question 2

In a balanced ecosystem, if the population of a prey species increases, what is the typical effect on the population of its predator species?

Accepted Answer

The predator population increases.

Answer

The predator population decreases.

Answer

The predator population remains unchanged.

Answer

The predator population first decreases and then increases.

Question 3

What is the term for the process by which energy from the sun is converted into chemical energy?

Accepted Answer

Photosynthesis

Answer

Respiration

Answer

Fermentation

Answer

Decomposition

Question 4

What is the term for the non-living components of an ecosystem?

Accepted Answer

Abiotic factors

Answer

Biotic factors

Answer

Limiting factors

Answer

Carrying capacity

Question 5

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

Accepted Answer

Cosmic factors

Answer

Biotic factors

Answer

Abiotic factors

Answer

Anthropogenic factors

Question 6

In a food web, the arrows represent the:

Accepted Answer

Direction of energy flow

Answer

Nutrient cycling pathways

Answer

Competitive relationships between species

Answer

Mutualistic interactions among species

Question 7

Which primary source provides the majority of energy for most ecosystems on Earth?

Accepted Answer

Light energy

Answer

Chemical energy

Answer

Heat energy

Answer

Electrical energy

Question 8

The term 'ecological niche' describes:

Accepted Answer

The unique functional role of an organism within an ecosystem

Answer

The specific physical location where an organism is found

Answer

The population size of a particular species

Answer

The genetic diversity within a species

Question 9

Which type of interspecific interaction benefits one species without affecting the other?

Accepted Answer

Commensalism

Answer

Mutualism

Answer

Parasitism

Answer

Predation

Question 10

Keystone species are important because they:

Accepted Answer

Have a disproportionate impact on their ecosystem relative to their abundance

Answer

Are the most abundant species in their ecosystem

Answer

Control the majority of energy flow within their ecosystem

Answer

Are the only species that can photosynthesize in their ecosystem

Question 11

Competition is a key factor influencing the distribution and survival of species within an ecosystem. Explain how competition shapes these aspects of ecological communities.

Accepted Answer

Competition promotes species diversity by driving adaptation and niche specialization.

Answer

Competition inevitably leads to the extinction of weaker species.

Answer

Competition has minimal influence on species distribution and survival.

Answer

Competition solely benefits dominant species, reducing biodiversity.

Question 12

How does increased biodiversity contribute to an ecosystem's stability and resilience?

Accepted Answer

Enhances ecosystem services and adaptability to environmental changes.

Answer

Increases competition among species, reducing stability.

Answer

Reduces resource specialization and niche partitioning.

Answer

Leads to the dominance of a few species.

Question 13

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

Accepted Answer

Climate

Answer

Producers

Answer

Consumers

Answer

Decomposers

Question 14

In a food chain, which organism occupies the highest trophic level?

Accepted Answer

Tertiary consumers

Answer

Producers

Answer

Primary consumers

Answer

Secondary consumers

Question 15

Which biogeochemical cycle involves the conversion of atmospheric nitrogen into usable forms by bacteria?

Accepted Answer

Nitrogen cycle

Answer

Carbon cycle

Answer

Oxygen cycle

Answer

Water cycle

Question 16

What is the primary function of decomposers in an ecosystem?

Accepted Answer

Breaking down dead organisms and recycling nutrients

Answer

Producing food

Answer

Consuming other organisms

Answer

Fixing nitrogen

Question 17

What is the term for the interconnected network of feeding relationships within an ecosystem?

Accepted Answer

Food web

Answer

Trophic pyramid

Answer

Nutrient cycle

Answer

Biosphere

Question 18

How does climate change affect ecosystem stability, biodiversity, and the services ecosystems provide?

Accepted Answer

Climate change can disrupt ecosystem balance, reduce biodiversity, and impair ecosystem services.

Answer

Climate change has no significant impact on these aspects.

Answer

Climate change mainly affects marine ecosystems.

Answer

Climate change has no impact on ecosystem services, as they are resistant to environmental changes.

Question 19

Identify the component that is NOT part of an ecosystem?

Accepted Answer

Atmosphere

Answer

Producers

Answer

Consumers

Answer

Decomposers

Question 20

In a food chain, which organism occupies the highest level, consuming other organisms?

Accepted Answer

Tertiary consumers

Answer

Producers

Answer

Primary consumers

Answer

Secondary consumers

Question 21

The process by which plants utilize sunlight to convert carbon dioxide and water into glucose is known as:

Accepted Answer

Photosynthesis

Answer

Respiration

Answer

Decomposition

Answer

Transpiration

Question 22

The carrying capacity of an ecosystem refers to:

Accepted Answer

The maximum population size that can be sustained

Answer

The rate at which population size increases

Answer

The number of predators in the ecosystem

Answer

The amount of food available

Question 23

Which of the following is an example of a living component within an ecosystem?

Accepted Answer

Plants

Answer

Temperature

Answer

Rainfall

Answer

Wind

Question 24

The process by which organic matter is broken down into simpler substances is referred to as:

Accepted Answer

Decomposition

Answer

Respiration

Answer

Transpiration

Answer

Photosynthesis

Question 25

Within an ecosystem, what is the most likely impact of an increase in predator population?

Accepted Answer

Decrease in prey population

Answer

Increase in prey population

Answer

No significant change in prey population

Answer

Increase in both predator and prey populations

Question 26

What is the primary function of decomposers in an ecosystem?

Accepted Answer

Break down organic matter into nutrients

Answer

Produce organic matter for producers

Answer

Consume other organisms for energy

Answer

Convert sunlight into chemical energy

Question 27

How are producers and consumers fundamentally different in an ecosystem?

Accepted Answer

Producers create their own food, while consumers obtain energy from other organisms

Answer

Consumers create their own food, while producers obtain energy from other organisms

Answer

Producers are always plants, while consumers are always animals

Answer

Consumers are always larger than producers

Question 28

Which of the following best describes ecological succession?

Accepted Answer

The gradual replacement of one community of organisms by another over time

Answer

The rapid change of an ecosystem from one state to another

Answer

The decrease in biodiversity over time

Answer

The increase in the number of trophic levels in an ecosystem

Question 29

In a well-balanced ecosystem, the total amount of energy available to consumers:

Accepted Answer

Remains constant

Answer

Increases over time

Answer

Decreases over time

Answer

Varies unpredictably

Question 30

Which of the following is a primary producer, forming the foundation of most ecosystems?

Accepted Answer

Plants

Answer

Bacteria

Answer

Fungi

Answer

Animals

Question 31

The process through which plants harness light energy to produce glucose, a form of chemical energy, is known as:

Accepted Answer

Photosynthesis

Answer

Respiration

Answer

Decomposition

Answer

Nitrification

Question 32

The primary agents responsible for decomposing organic matter in an ecosystem are:

Accepted Answer

Bacteria and fungi

Answer

Plants

Answer

Animals

Answer

Viruses

Question 33

In a grassland ecosystem, an example of a food chain is:

Accepted Answer

Grass → Insect → Bird

Answer

Tree → Squirrel → Hawk

Answer

Algae → Zooplankton → Fish

Answer

Bacteria → Worm → Spider

Question 34

Within the nitrogen cycle, what is the primary function of nitrifying bacteria?

Accepted Answer

Convert ammonia into nitrate, a form usable by plants

Answer

Decompose organic matter, releasing nitrogen into the soil

Answer

Convert atmospheric nitrogen into a form usable by plants

Answer

Remove nitrogen from the ecosystem by converting it into nitrogen gas

Question 35

How does a reduction in biodiversity impact crucial ecosystem services like nutrient cycling and pollination?

Accepted Answer

Biodiversity loss can slow nutrient cycling, potentially reducing soil fertility.

Accepted Answer

Pollination, vital for plant reproduction, can be hindered by the decline of pollinator species.

Answer

Ecosystem services are unaffected by biodiversity changes.

Answer

Biodiversity loss has no significant impact on ecosystem services.

Question 36

Deforestation negatively impacts ecosystem services. How does it affect water filtration and carbon sequestration?

Accepted Answer

Decreases water filtration and carbon sequestration.

Answer

Increases water retention and carbon storage.

Answer

Improves air quality and biodiversity.

Answer

Enhances soil stability and water purification.

Question 37

Biodiversity is vital for an ecosystem's ability to bounce back from disruptions. How does losing biodiversity affect this resilience?

Accepted Answer

Biodiversity helps because different species react differently to disruptions.

Answer

Less biodiversity helps because there's less competition between species.

Answer

Losing biodiversity doesn't really affect how well an ecosystem recovers.

Question 38

Which of the following is **not** a vital component of an ecosystem?

Accepted Answer

Human-made structures

Answer

Living organisms

Answer

Energy flow within the system

Answer

Non-living physical environment

Question 39

Photosynthesis is the process by which organisms convert light energy into chemical energy. Which of the following describes this process?

Accepted Answer

Plants and some bacteria use sunlight to synthesize glucose molecules.

Answer

Decomposers break down dead organisms into organic compounds.

Answer

Consumers obtain energy by consuming producers or other consumers.

Answer

Animals and fungi absorb glucose directly from the environment.

Question 40

In an ecosystem, a primary consumer is an organism that:

Accepted Answer

Feeds directly on producers.

Answer

Feeds on other consumers.

Answer

Feeds on both producers and consumers.

Answer

Breaks down dead organisms.

Question 41

The primary source of energy for the majority of ecosystems on Earth is:

Accepted Answer

The sun

Answer

Chemical reactions within decomposers

Answer

Geothermal heat

Answer

Wind

Question 42

Which characteristic is indicative of a stable ecosystem?

Accepted Answer

Relative stability in the size of populations of different species.

Answer

Absence of competition between species.

Answer

Minimal nutrient cycling and exchange between organisms.

Answer

Rapid and extreme fluctuations in population numbers.

Question 43

The process by which microorganisms break down organic matter into simpler substances is known as:

Accepted Answer

Decomposition

Answer

Denitrification

Answer

Respiration

Answer

Nitrification

Question 44

The ecological pyramid that represents the number of individuals at each trophic level is called a:

Accepted Answer

Pyramid of numbers

Answer

Pyramid of biomass

Answer

Pyramid of energy

Question 45

Which of the following biomes is characterized by abundant rainfall, high humidity, and consistently warm temperatures throughout the year?

Accepted Answer

Tropical rainforest

Answer

Desert

Answer

Temperate forest

Answer

Tundra

Question 46

The process by which plants release water vapor into the atmosphere through their leaves is known as:

Accepted Answer

Transpiration

Answer

Evaporation

Answer

Condensation

Answer

Precipitation

Question 47

Which of the following is **not** a fundamental component of an ecosystem?

Accepted Answer

Weather patterns

Answer

Consumers

Answer

Decomposers

Answer

Producers

Question 48

The process by which producers harness sunlight to create energy-rich molecules is called:

Accepted Answer

Photosynthesis

Answer

Respiration

Answer

Chemosynthesis

Answer

Glycolysis

Question 49

Select the organism that is considered a primary consumer:

Accepted Answer

Grasshopper

Answer

Mushroom

Answer

Cheetah

Answer

Owl

Question 50

As energy flows through trophic levels within an ecosystem, what is the general trend?

Accepted Answer

Energy is lost

Answer

Energy remains constant

Answer

Energy is gained

Answer

Energy is created

Question 51

Which of the following factors is considered **biotic** in an ecosystem?

Accepted Answer

Competition for resources

Answer

Temperature fluctuations

Answer

Wind speed

Question 52

Identify a primary impact of human activities on ecosystems:

Accepted Answer

Habitat destruction

Answer

Increased species diversity

Answer

Stable climate conditions

Answer

Enhanced air quality

Question 53

The term 'ecological niche' refers to:

Accepted Answer

The specific role and requirements of an organism within an ecosystem

Answer

The physical habitat of an organism

Answer

The genetic makeup of an organism

Question 54

Which characteristic is indicative of a stable ecosystem?

Accepted Answer

Relatively stable population sizes

Answer

Rapid population growth

Answer

Frequent extreme weather events

Question 55

Identify the primary source of energy for most ecosystems on Earth:

Accepted Answer

Sunlight

Answer

Wind power

Answer

Tidal energy

Answer

Geothermal energy