47. The pistil of an angiosperm typically consists of three parts from top to bottom. They are, in order: (A) Anther, filament, receptacle (B) Stigma, style, ovary (C) Petal, sepal, pedicel (D) Ovule, placenta, carpel

48. Nitrogen gas (N₂) in the soil cannot be directly used by plants and must undergo nitrogen fixation. In nature, the process of converting N₂ to ammonia (NH₃) primarily relies on the participation of which of the following organisms? (A) Mycorrhizal fungi (B) Nitrogen-fixing bacteria and cyanobacteria (C) Algae in lichens (D) Digestive enzymes of carnivorous plants

47. The pistil of an angiosperm typically consists of three parts from top to bottom. They are, in order:
(A) Anther, filament, receptacle
(B) Stigma, style, ovary
(C) Petal, sepal, pedicel
(D) Ovule, placenta, carpel

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