Ecosystem Ecology: Energy Flow, Nutrient Cycling, and Food Webs

Question 1

In most terrestrial ecosystems on Earth, what is the primary energy source?

Accepted Answer

Sunlight

Answer

Fossil fuels

Answer

Wind

Answer

Nuclear reactions

Question 2

What primary role do decomposers perform within an ecosystem?

Accepted Answer

Breaking down deceased organisms

Answer

Producing oxygen

Answer

Consuming primary producers

Answer

Fixing nitrogen

Question 3

Which of the following diagrams best represents a pyramid of biomass?

Accepted Answer

Depiction of the biomass quantity at each trophic level

Answer

Depiction of the number of organisms at each trophic level

Answer

Depiction of the energy quantity at each trophic level

Answer

Depiction of the number of individuals within each species

Question 4

What ecological term describes the total quantity of organic matter within an ecosystem?

Accepted Answer

Biomass

Answer

Productivity

Answer

Biodiversity

Answer

Carrying capacity

Question 5

What is the ecological term for a complex web of interconnected food chains within an ecosystem?

Accepted Answer

Food web

Answer

Trophic network

Answer

Ecological pyramid

Answer

Community structure

Question 6

Identify the correct sequence of energy flow within an ecosystem:

Accepted Answer

Producers → Primary Consumers → Secondary Consumers → Top Predators → Decomposers

Answer

Decomposers → Producers → Primary Consumers → Secondary Consumers → Top Predators

Answer

Secondary Consumers → Primary Consumers → Producers → Decomposers → Top Predators

Answer

Top Predators → Secondary Consumers → Primary Consumers → Producers → Decomposers

Question 7

In a typical food chain, an organism that feeds directly on producers is known as a/an:

Accepted Answer

Primary consumer

Answer

Decomposer

Answer

Secondary consumer

Answer

Apex predator

Question 8

An ecological pyramid that depicts the amount of energy present at each trophic level is referred to as a:

Accepted Answer

Energy pyramid

Answer

Biomass pyramid

Answer

Number pyramid

Answer

Ecological efficiency pyramid

Question 9

Decomposition plays a crucial role in ecosystems by:

Accepted Answer

Releasing nutrients back into the soil

Answer

Eliminating harmful pollutants

Answer

Providing nourishment for scavengers

Answer

Regulating Earth's climate

Question 10

The primary goal of ecosystem management is to:

Accepted Answer

Preserve the balance and integrity of ecosystems

Answer

Maximize economic benefits from ecosystems

Answer

Eradicate pests and diseases

Answer

Restore degraded ecosystems

Question 11

How do decomposers help recycle nutrients in an ecosystem?

Accepted Answer

Decomposers release nutrients into the soil by breaking down dead plants and animals.

Answer

Decomposers take nutrients from the air and soil.

Answer

Decomposers make their own food through photosynthesis.

Question 12

Approximately what percentage of energy is transferred from one trophic level to the next?

Accepted Answer

10%

Answer

50%

Answer

75%

Answer

90%

Question 13

Which organism is the primary producer in an ecosystem?

Accepted Answer

Plants

Answer

Herbivores

Answer

Carnivores

Answer

Decomposers

Question 14

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

Accepted Answer

Hawk

Answer

Grass

Answer

Rabbit

Answer

Fox

Question 15

Which of the following is NOT a type of ecological pyramid?

Accepted Answer

Pyramid of soil

Answer

Pyramid of numbers

Answer

Pyramid of biomass

Answer

Pyramid of energy

Question 16

The process by which nutrients are returned to the soil is known as:

Accepted Answer

Decomposition

Answer

Nitrogen fixation

Answer

Photosynthesis

Answer

Respiration

Question 17

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

Accepted Answer

Ecology

Answer

Environmental science

Answer

Biology

Answer

Zoology

Question 18

Which of the following is NOT a component of the carbon cycle?

Accepted Answer

Nitrogen

Answer

Plants

Answer

Animals

Answer

Fossil fuels

Question 19

In a food chain, the primary consumer is the organism that:

Accepted Answer

Feeds on producers

Answer

Feeds on carnivores

Answer

Does not feed on other organisms

Answer

Feeds on omnivores

Question 20

Which process returns nutrients to the soil?

Accepted Answer

Decomposition

Answer

Respiration

Answer

Photosynthesis

Answer

Transpiration

Question 21

Which type of ecosystem is characterized by a stable community of organisms?

Accepted Answer

Climax community

Answer

Pioneer community

Answer

Seral community

Answer

Transitional community

Question 22

What is the graphical representation of the relative abundance of organisms at different trophic levels called?

Accepted Answer

Ecological pyramid

Answer

Community structure

Answer

Trophic cascade

Answer

Food web

Question 23

Which type of symbiotic relationship involves mutual benefit for both organisms?

Accepted Answer

Mutualism

Answer

Amensalism

Answer

Parasitism

Answer

Commensalism

Question 24

What is the term for the process by which energy is transferred from one trophic level to another?

Accepted Answer

Energy flow

Answer

Nutrient cycling

Answer

Photosynthesis

Answer

Decomposition

Question 25

Which characteristic is associated with a keystone species?

Accepted Answer

Disproportionately large impact on the ecosystem relative to its abundance

Answer

Found in all types of ecosystems

Answer

Always the top predator in the food chain