Which of the following is true for endarch type of primary xylem?
Protoxylem lies towards the periphery of the organ
Metaxylem lies towards the periphery of the organ
Metaxylem lies towards the pith of the organ
Protophloem lies towards the pith of the organ
The only plant cells without nuclei among the following are
$A$ : Sieve tubes and companion cells are related ontogenetically.
$R$ : Both develop from same mother cell.
Xylem tissue is composed of
The tissue which is living but does not possess nucleus in mature stage is