Is sieve tube of phloem livivg or non living? ans with explaination.

Sieve tubes are long, tubular structures. They are living cells but have lost their nuclei to become specialised for the translocation of food. I ts not that the sieve tubes do not have nucleus. They develop initially as cells with nuclei but as they attain maturity, they lose their nucleus completely. This is an adaptations for its function to translocate the food.

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