In the field of biodiversity, estimating the number of prokaryotes (bacteria and archaea) is far more difficult than estimating the number of plants or animals. Here is the breakdown of why these statements are categorized this way:

Analysis of the Statements

False: While we don't know the nutritional needs of many bacteria, "nutritional requirements" is a subset of why we can't grow them in a lab. In biology textbooks (specifically following the NCERT/standard curriculum), this is usually not cited as the primary reason for the inability to estimate species numbers.

True: Conventional taxonomic methods (classifying organisms based on physical traits or simple biological characteristics) are not suitable for identifying microbial species. Many microbes look identical under a microscope but are genetically unique.

True: This is the most significant hurdle. It is estimated that less than 1% of bacterial species can be grown (cultured) using current laboratory media. If we can't grow them, we can't easily study or classify them.

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