Question 54
Why are xylem and phloem called complex tissues? How are they different from one other?
Complex tissues are made of more than one type of permanent cells. Both xylem and phloem consists of more than one type of cells, which coordinate to perform a common function.
XylemPhloemConsists of tracheids, vessels, xylem parenchymaConsist of sieve tubes, companion cell, phloemand xylem fibers.parenchyma and phloem fibers.They transport water and minerals vertically fromThey translocate food from leaves to all other parts ofsoil to aerial parts of the plant. Its movement is unidirectional.the plant. Its movement is bidirectional.Most of the cells except xylem parenchyma areMost of the cells except phloem fibres are livingdead cells.cells.