Topic 6B

Question 1

What is the primary source of energy for Earth’s ecosystems?

Answer 1

The Sun

Question 2

True or False: Energy can be created and destroyed.

Answer 2

False

Question 3

Fill in the blank: The process by which plants convert sunlight into chemical energy is called ______.

Answer 3

photosynthesis

Question 4

What are the two main types of energy transfer in ecosystems?

Answer 4

Heat transfer and nutrient cycling

Question 5

What is the role of producers in an ecosystem?

Answer 5

Producers convert solar energy into chemical energy through photosynthesis.

Question 6

Define ‘trophic level’.

Answer 6

A trophic level is a position in a food chain or food web, representing the flow of energy and nutrients.

Question 7

Which trophic level do herbivores belong to?

Answer 7

Primary consumers

Question 8

What is the term for organisms that break down dead organic matter?

Answer 8

Decomposers

Question 9

Multiple Choice: Which of the following is NOT a biogeochemical cycle? A) Water cycle B) Carbon cycle C) Energy cycle D) Nitrogen cycle

Answer 9

C) Energy cycle

Question 10

What is the main function of the nitrogen cycle in ecosystems?

Answer 10

To convert nitrogen into forms usable by living organisms.

Question 11

True or False: Energy flows in one direction through an ecosystem.

Answer 11

True

Question 12

What is the significance of the 10% rule in energy transfer?

Answer 12

Only about 10% of the energy from one trophic level is transferred to the next.

Question 13

Fill in the blank: The ______ cycle involves the movement of water through the environment.

Answer 13

water

Question 14

What process returns carbon to the atmosphere?

Answer 14

Respiration and combustion

Question 15

Which nutrient cycle is primarily affected by human activities, such as the use of fertilizers?

Answer 15

Nitrogen cycle

Question 16

What is a food web?

Answer 16

A complex network of feeding relationships among organisms in an ecosystem.

Question 17

Multiple Choice: Which of the following is a secondary consumer? A) Grass B) Rabbit C) Fox D) Deer

Answer 17

C) Fox

Question 18

What is the purpose of the phosphorus cycle?

Answer 18

To recycle phosphorus through the environment, vital for DNA and ATP.

Question 19

True or False: All energy in an ecosystem originates from the soil.

Answer 19

False

Question 20

What is the main process by which energy is lost at each trophic level?

Answer 20

Heat loss through metabolic processes

Question 21

Fill in the blank: The ______ cycle is crucial for the synthesis of proteins in living organisms.

Answer 21

nitrogen

Question 22

What are the two primary components of the water cycle?

Answer 22

Evaporation and precipitation

Question 23

Define ‘biomass’.

Answer 23

The total mass of living matter within a given area or volume.

Question 24

What is the primary role of autotrophs in the carbon cycle?

Answer 24

To absorb carbon dioxide during photosynthesis.

Question 25

True or False: Decomposers are essential for recycling nutrients in ecosystems.

Answer 25

True

Question 26

What happens to energy as it moves up the trophic levels?

Answer 26

It decreases due to energy loss at each level.

Question 27

Fill in the blank: In the nitrogen cycle, bacteria convert nitrogen gas into ______.

Answer 27

ammonia

Question 28

What is the main driving force of the water cycle?

Answer 28

Solar energy

Question 29

Multiple Choice: Which of the following is NOT a greenhouse gas? A) Carbon dioxide B) Methane C) Nitrogen D) Water vapor

Answer 29

C) Nitrogen

Question 30

What is the role of fungi in nutrient cycles?

Answer 30

Fungi decompose organic matter and recycle nutrients back into the soil.

Question 31

What is meant by 'energy efficiency' in an ecosystem?

Answer 31

The ratio of energy transferred from one trophic level to the next.

Question 32

True or False: The amount of energy available decreases as it moves up the food chain.

Answer 32

True

Question 33

What is the process by which excess nutrients run off into water bodies, causing algal blooms?

Answer 33

Eutrophication

Question 34

Fill in the blank: The ______ cycle is essential for the formation of DNA and RNA.

Answer 34

phosphorus

Question 35

Define 'carbon sink'.

Answer 35

A natural reservoir that stores carbon-containing compounds for an indefinite period.

Question 36

What is the primary source of nitrogen for plants?

Answer 36

Ammonium and nitrate in the soil

Question 37

Multiple Choice: Which of the following processes contributes to the carbon cycle? A) Photosynthesis B) Respiration C) Decomposition D) All of the above

Answer 37

D) All of the above

Question 38

What is the significance of keystone species in ecosystems?

Answer 38

Keystone species have a disproportionately large impact on their environment relative to their abundance.

Question 39

True or False: Energy is recycled in ecosystems.

Answer 39

False

Question 40

What is the term for the maximum population size that an ecosystem can sustainably support?

Answer 40

Carrying capacity

Question 41

Fill in the blank: The ______ cycle is closely linked to the water cycle due to the movement of water through plants.

Answer 41

carbon

Question 42

What are the two primary processes of the phosphorus cycle?

Answer 42

Weathering of rocks and uptake by plants

Question 43

What is the role of zooplankton in aquatic ecosystems?

Answer 43

Zooplankton are primary consumers that feed on phytoplankton.

Question 44

Multiple Choice: Which nutrient cycle is most affected by deforestation? A) Carbon cycle B) Nitrogen cycle C) Phosphorus cycle D) Water cycle

Answer 44

A) Carbon cycle

Question 45

What is the main consequence of excessive nutrient runoff into aquatic systems?

Answer 45

Algal blooms and subsequent oxygen depletion.

Question 46

True or False: All organisms utilize the same nutrient cycles.

Answer 46

True