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Q.
In Angioperms all the four microspores of tetrad
are covered by a layer which is made up of :
Sexual Reproduction in Flowering Plants
Solution:
Callose wall surrounds the sporocytes during the meiotic stage. It provides an isolation barrier sealing off one meiotic cell (megaspore mother cell) from another. Hence it acts as a molecular filter isolating the developing microspores from the influence of the surrounding diploid tissue or sister spores.