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Q.
The structure which protect the archegonium in Marchantia is
Plant Kingdom
Solution:
After fertilisation, the stalk of the archegoniophore begins to elongate accompanied with this is rapid growth of the upper surface of the receptacle. With more growth the archegonia get inverted and this inversion is accompanied by the development of a plate like tissue on either side of each row of archegonia. It is called the perichaetium or the involucre. It is single cell layer in thickness and protects the archegonia.