Which term describes the slender filaments that extend into the soil to increase surface area for nutrient absorption?

• A. Mycelium
• B. Nematodes
• C. Sclerotia
• D. Hyphae

Answer: (D)

In fungi, nutrient uptake happens through threadlike extensions that probe the soil. These slender filaments are called hyphae. They extend and branch into soil microspaces, greatly increasing the surface area available for absorption. Hyphae secrete enzymes to break down complex organic matter outside the cell and then absorb the resulting nutrients. When many hyphae grow together, they form a network called a mycelium, which is the whole mass rather than the individual filaments. The other terms describe different fungal structures or organisms: mycelium is the network itself, sclerotia are hardened survival structures, and nematodes are microscopic worms, not fungal filaments. So the described slender filaments that extend into soil to boost nutrient absorption are hyphae.