What do diatoms represent?
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Answer: B. Soil Algae
Explanation
Diatoms are a major group of microscopic, single-celled algae belonging to the bacillariophytes. They feature unique cell walls made of hydrated silicon dioxide known as frustules. These photosynthetic algae inhabit aquatic ecosystems and damp soil environments worldwide. Microscopic soil algae contribute to organic matter accumulation and biological crust stability. Diatoms reproduce primarily through cell division and play a major role in global carbon fixation. Their fossilized cell walls accumulate as diatomaceous earth deposits over geological time.
Soil ecologists study diatom communities to assess moisture dynamics and wetland health indicators. Diatomaceous earth is harvested commercially for use in filtration, pest control, and abrasives. Aquatic and soil diatoms form a vital base for microscopic food webs in various ecosystems. Option A is incorrect because diatoms are photosynthetic algae rather than heterotrophic fungi. Option C is wrong because diatoms are eukaryotic algae instead of single-celled prokaryotic bacteria. Option D is invalid since diatoms are well-classified microscopic soil and water algae.
- Subject
- Agriculture
- Category
- Agriculture
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- —
- Difficulty
- medium
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