Carbon Cycle MCQ Questions and Answers Pdf :

1. In an ecosystem, the main form of carbon cycling between the inorganic environment and the biological community is______

A. carbon dioxide

B. Carbonate

C. carbonic acid

d. glucose

Answer: A

2. The source of carbon to plants in the carbon cycle is_________

A. fossil fuels

B. carbonate rocks

C. atmospheric carbon dioxide

D. all of the above

Answer: C

3. The role of bacteria in the carbon cycle is______

A. Breakdown of organic compounds

B. Chemosynthesis

C. Photosynthesis

D. Assimilation of nitrogen compounds

Answer: A

4. Which of the statements about the carbon cycle are false_______

A. produce greenhouse gases

B. Requires energy to drive

C. Does not depend on water

D. global

Answer: C

5. It is a producer in the ecosystem and belongs to prokaryotes from the perspective of cell structure. It plays an important role in the carbon cycle of the ecosystem.

A. Cyanobacteria

B. bacteria

C. rice

D. Virus

Answer: A

6. Which factor contributes to the carbon cycle_______

A. fossil fuel combustion

B. respiration

C. photosynthesis

D. all of these

Answer: D

7. In an ecosystem, the process of releasing carbon dioxide into the atmosphere is______

A. photosynthesis

B. respiration

C. dissimilation

D. both B and C

Answer: D

8. The “substance” in the material cycle of the ecosystem refers to_______

A. CO 2

b. Elements that make up the natural world

C. The basic elements that makeup living organisms

D. proteins that makeup living organisms

Answer: C

9. Material cycling in an ecosystem occurs in_______

A. between producers and consumers

B. between different biological communities

C. between producers and decomposers

D. Between community and inorganic environment

Answer: D

10. Respiration and photosynthesis are central to this process_______

A. nitrogen cycle

B. phosphorous cycle

C. carbon cycle

D. sulfur cycle

Answer: C

11. The primary means by which carbon dioxide can be released into the atmosphere to sustain the carbon cycle in any ecosystem is___________

A. The burning of fossil fuels

B. The decomposition of chemical plants releases

C. biological respiration

d. decomposition of carbonate

Answer: C

12. The role of bacteria in the carbon cycle is________

A. breakdown of organic compounds

B. chemosynthesis

C. photosynthesis

D. assimilation of nitrogen compounds

Answer: D

13. Which of the following is NOT part of the way carbon is returned to the atmosphere in a biome________

A. biological respiration

B. Chemical energy synthesis by some bacteria

C. Decomposition of decomposers

D. Forest fire

Answer: B

14. Which of the following statements about the carbon cycle in the biosphere is false________

A. The carbon cycle is accompanied by the flow of energy

B. Decomposers do not participate in the carbon cycle process in the biosphere

C. Photosynthesis and respiration are closely related to the carbon cycle

D. The predominant form of carbon cycling between biological communities and the inorganic environment is CO2

Answer: C

15. In the carbon cycle, the physiological functions that bring carbon from the inorganic environment into the biological community are

① respiration 

② photosynthesis 

③ feeding 

④ chemical energy synthesis 

⑤ nitrification 

⑥ denitrification

A. ①②

B. ③④

C. ②④

D. ⑤⑥

Answer: C

16. Which of the following statements about carbon cycling in ecosystems is correct____________

A. The carbon cycle refers to the process by which C is transferred along the food chain in the biological community

B. In terms of the carbon cycle, the most important component of the ecosystem is the decomposer

C. The carbon cycle is mainly carried out in the form of CO 2, which has global characteristics

D. Low carbon economy will inevitably slow down economic development

Answer: C

17. From which stages does carbon cycling occur?

A. Dead organisms → Living organisms → Oceans

B. Atmosphere → Living organisms → Dead organisms

C. Oceans → Atmosphere → Dead organisms

D. Atmosphere → Oceans → Living organisms → Dead organisms

Answer: D

18. This carbon isotope is radioactive and very rare________

A. Carbon – 11

B. Carbon – 12

C. Carbon – 13

D. Carbon – 14

Answer: D