- A They actively compete against host tree roots for water and mineral nutrients in soil, a competitive relationship rather than the mutualistic exchange that actually occurs
- B Connect roots of different trees, enabling carbon and nutrient transfer between trees (symbiotic network, sometimes called wood wide web)
- C They function mainly to absorb water from the soil, with little other ecological role, ignoring their well-documented role in inter-tree carbon and nutrient transfer
- D They form symbiotic associations mainly with young seedling trees, not mature ones, excluding the well-documented associations they form with largely mature canopy trees
Correct answer: B. Connect roots of different trees, enabling carbon and nutrient transfer between trees (symbiotic network, sometimes called wood wide web)
Explanation: Mycorrhizal networks: fungal hyphae connect multiple trees. Carbon, phosphorus, and nitrogen can flow between trees (source to sink). Mother trees may preferentially support kin through these networks.
Concept context
Ecosystems, food chains, energy flow, nutrient cycles, biodiversity, and conservation.