What do sieve tube cells actually do? Is it a filtering job or something else?
A. They are part of the phloem tissue that is involved in transporting sugars and other dissolved solutes around the plant. They don’t actually filter. The “holes” that they have simply allow these substances to move from one sieve cell to the other more easily, rather than having to cross plasma membranes all the time. So, sieve tube cells act likely a pipeline. Unlike xylem tissue, they are living cells but because they have most of their organelles removed they rely on companion cells for energy and proper functioning. VM Thankyou very much. It all makes sence now!
