๐Ÿ›ก๏ธ

Content Protected

Screenshots and recording are not allowed.

Click anywhere or refocus to continue

Nutrient Cycling - Carbon and Phosphorus Cycle - Unsolved Practice Set

Class 12

Chapter: Ecosystem | Topic: Nutrient Cycling Carbon and Phosphorus Cycle

Study Material.
Class 12

NUTRIENT CYCLING - CARBON AND PHOSPHORUS CYCLE - UNSOLVED PRACTICE SET

Topic: Nutrient Cycling Carbon and Phosphorus Cycle

Time: 30 mins | Marks: 30 | Difficulty: Medium

Multiple Choice Questions

Q1. Biogeochemical cycles refer to the pathways by which:

  1. Energy flows unidirectionally through an ecosystem
  2. Nutrients and elements circulate between living organisms and the physical environment
  3. Species evolve over time
  4. Ecosystems undergo succession

Q2. Biogeochemical cycles are generally classified into which two broad types?

  1. Fast cycles and slow cycles only
  2. Gaseous cycles and sedimentary cycles
  3. Aquatic cycles and terrestrial cycles only
  4. Producer cycles and consumer cycles

Q3. The main reservoir for the carbon cycle, from which producers obtain carbon for photosynthesis, is:

  1. Soil minerals only
  2. Atmospheric and dissolved oceanic carbon dioxide
  3. Fossilised rock formations only
  4. Animal tissue

Q4. Unlike the carbon cycle, the phosphorus cycle is considered primarily a:

  1. Gaseous cycle, with a large atmospheric component
  2. Sedimentary cycle, with rocks and minerals as the main reservoir, and little atmospheric involvement
  3. Cycle with no biological significance
  4. Cycle that occurs only in aquatic ecosystems

Q5. Human activities such as burning fossil fuels have significantly impacted the carbon cycle mainly by:

  1. Decreasing atmospheric carbon dioxide levels
  2. Increasing atmospheric carbon dioxide levels, contributing to climate change concerns
  3. Having no measurable effect on atmospheric carbon levels
  4. Completely halting the natural carbon cycle

Short Answer Questions

Q6. Define a biogeochemical cycle, and differentiate between gaseous and sedimentary cycles.

Q7. Briefly describe the main pathway of the carbon cycle, mentioning at least two key processes involved.

Q8. Why is the phosphorus cycle classified as a sedimentary cycle rather than a gaseous cycle?

Q9. Mention one significant way in which human activity has impacted the natural carbon cycle.

Long Answer Questions

Q10. Describe the carbon cycle in detail, explaining how carbon moves between the atmosphere, living organisms, and other reservoirs such as oceans and fossil fuels.

Q11. Describe the phosphorus cycle in detail, explaining the role of rock weathering, plant uptake, and sedimentation in this nutrient cycle.

APPLICATION / ANALYSIS

Q12. Over the past century, atmospheric carbon dioxide levels have risen significantly, largely due to increased burning of fossil fuels and deforestation. Explain, using your understanding of the carbon cycle, how these two human activities contribute to this rise in atmospheric CO2.

Q13. A farmer notices that crop yields in a particular field have declined over several growing seasons without the addition of phosphorus-containing fertilisers. Explain, using your understanding of the phosphorus cycle, why phosphorus depletion in agricultural soil is a common long-term concern, given that phosphorus lacks a significant atmospheric replenishment pathway.


Total: 30 Marks | Time: 30 mins

Explore more topics in Ecosystem