Nutrient Cycling MCQs (Quiz 4) Posted on May 29, 2026Author agropublishers 0 1. Which of the following is an abiotic component? Atmosphere Herbivores Fungi Algae 2. Which of the following correctly distinguishes a nutrient source from a nutrient sink? A source and sink perform identical functions at different rates A source releases more nutrients than it absorbs; a sink absorbs more than it releases A source permanently removes nutrients from circulation; a sink temporarily stores them A source absorbs more nutrients than it releases; a sink does the opposite 3. Nutrient immobilization refers to the process in which _________________ Nutrients are chemically destroyed by soil microorganisms Nutrients are permanently removed from circulation via surface runoff All available soil nutrients are exhausted by plant uptake Nutrients become temporarily unavailable as they are incorporated into living biomass or organic matter 4. The primary reservoir/s for the sedimentary phosphorus cycle include __________________ Rocks and soil Oceans Atmosphere Living organisms 5. Which of the following correctly distinguishes nitrogen fixation from nitrification? Nitrogen fixation is carried out by the same bacteria responsible for denitrification Nitrogen fixation converts atmospheric N₂ into ammonia using the nitrogenase enzyme; nitrification converts ammonia into nitrites and then nitrates through oxidation Nitrogen fixation converts ammonia to nitrates; nitrification converts nitrates to nitrogen gas Both processes begin with atmospheric nitrogen but produce different end products 6. Which of the following nutrient cycles is most directly tied to global climate change and the greenhouse effect? Phosphorus cycle Nitrogen cycle Carbon cycle Water cycle 7. What happens to energy and nutrients after they pass through a food chain? Energy is recycled by decomposers; nutrients are lost as heat Both are permanently lost from the ecosystem after use Both are recycled back to producers without any loss Energy is lost as heat at each trophic level, while nutrients are returned to the environment by decomposers and reused 8. Which organism forms a symbiotic relationship with plant roots to significantly enhance the absorption of phosphorus and other immobile soil nutrients? Mycorrhizal fungi Nitrogen-fixing bacteria Cyanobacteria Earthworms 9. The primary result of weathering is _____________ Development of ocean currents Disintegration and decomposition of rocks and minerals Formation of new mountain ranges Conversion of sedimentary rocks into magma 10. Which process is classified as chemical weathering? Hydrolysis Root wedging Exfoliation Frost shattering Loading … Question 1 of 10
