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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
  1. Do all pollen grains remain viable for the same length of time? Support your answer with two suitable examples.
  2. How are pollen grains stored in pollen banks? State the purpose of storing pollen grains in these banks.
✓

Answer

  1. No; the pollen grains of different species remain viable for different periods of time.

e.g. pollen grains of cereals remain viable for less than 30 minutes whereas some members of Rosaceae, Leguminosae and Solanaceae retain the pollen viability for months.

  1. In the pollen banks, pollen grains are stored. In liquid nitrogen (at -196°C). Such stored pollen grains can be used for breeding programmes whenever necessary.

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