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Sexual Reproduction in Flowering Plants — BIOLOGY STD 12 Science — Question

Bihar BoardEnglish MediumSTD 12 ScienceBIOLOGYSexual Reproduction in Flowering Plants3 Marks
Question
Pollen grains are both useful and harmful. Justify the statement.
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Answer

Pollen grains of many species cause severe allergies and bronchial afflictions in some people often leading to chronic respiratory disorders—asthma, bronchitis etc. Parthenium or carrot grass that came into India as a contaminant with improved wheat has become worldwide in occurrence and causes pollen allergy.
Pollen grains are rich in nutrients. It has become a fashion is recent years to use pollen tablets as food supplements. In western countries, a large number of pollen products in the form of tablets and syrups are available in the market. Pollen cosumption has been claimed to increase the performance of athletes and race horses. 

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