Nutrient Cycling MCQs (Quiz 8) Posted on May 30, 2026Author agropublishers 0 1. Which of the following best explains why life on Earth is sustainable over geological timescales despite a fixed supply of nutrients? New nutrients are continuously generated through nuclear reactions in the Earth’s core Solar energy drives the continuous synthesis of new nutrient molecules from atmospheric gases Nutrients are imported from space through meteorite impacts at a sufficient rate Nutrients cycle repeatedly through biotic and abiotic components via biogeochemical cycles, whereas energy cannot be recycled, and is continuously supplied by solar input 2. Which statement best summarizes the ecological significance of weathering? It functions independently of ecosystems It only affects geological formations It only alters landscape appearance It links geology and ecology by releasing nutrients and supporting soil formation 3. Heavy rainfall following fertilizer application often leads to nutrient loss because ______________ It enhances leaching of soluble nutrients below the root zone It converts nutrients into gases It increases nutrient fixation in soil It promotes weathering of bedrock 4. During the decomposition of organic matter, bacteria break down proteins and nucleic acids. What nitrogenous product is directly released by this process? Ammonium ions (NH₄⁺) Urea Nitrite ions (NO₂⁻) Nitrate ions (NO₃⁻) 5. Which nutrient cycle is most dependent on weathering processes? Oxygen cycle Phosphorus cycle Nitrogen cycle Carbon cycle 6. Biological weathering may contribute to chemical weathering through ________________ Lowering atmospheric pressure Production of organic acids by organisms Increasing rock density Reduction of humidity 7. Lichens are ecologically important because they _________________ Initiate rock weathering and soil development Reduce mineral release Prevent soil formation Immobilize nutrients permanently 8. Which of the following best describes nutrient turnover in an ecosystem? Nutrients are permanently removed from circulation by soil sediments Nutrients flow in one direction from producers to decomposers Nutrients are continuously recycled through living organisms and the environment Nutrients are converted into rocks and stored underground 9. Coal, petroleum, and natural gas are considered major carbon reservoirs because they ________________ Store carbon that was fixed by photosynthesis millions of years ago Contain only inorganic carbon compounds Are produced directly from atmospheric CO₂ each year Continuously absorb atmospheric carbon dioxide 10. Which of the following best explains why root hair cells are well adapted for absorption in plants? They are covered in a thick waxy cuticle to prevent water loss They have a large surface area and thin walls, facilitating efficient uptake of water and ions from soil They are located above ground to access atmospheric moisture They contain chloroplasts to produce energy for mineral uptake Loading … Question 1 of 10
