Question

despite losing nuclei the mature sieve tube cells remain alive and function how does it happen​

Answer 1

Explanation:

Seive tubes are specialised cells which are modified in order to transport maximum water to the upper body this is the reason why Angiosperms are more efficient than gymnosperms in water conduction since on maturing these cells becomes perforated and lack of all the cell constituents like cytoplasm , vacuoles , nucleus.

The question arises that nucleus is the controlling system of cell yes that's correct but the function of nucleus is performed by Companion cells these cells are called sister cells they control all the activities which are performed by nucleus. so the answer is "Companion cells"

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