Question

How do sieve tubes manage to live in?

Answer 1

Each STM is a living cell. They have to be alive because phloem transport only occurs in living cells with intact, functioning plasma membranes. The cytoplasm of a sieve tube is continuous; where the STMs abut, there are many large pores connecting them.

Answer 2

The nucleus of companion cell is responsible for the activities of Sive tube cells or elements...