Identify $P$ and $Q$ in the given structures.

Read the components $a$ to $d$ given in the note and identify the correct sequence of components from the outside to the inside of a mature stem:
$(a)$ Secondary cortex
$(b)$ Wood (Secondary xylem)
$(c)$ Secondary phloem
$(d)$ Phellem (Cork)

Scaly bark is found in ...........

Which of the following tissues originate from ray initials of a cambium?

Tyloses,an outgrowth from ray or axial parenchyma cells into the lumen of a vessel,which partially or completely blocks the cavity,are present in:

Which of the following is true for the dicot roots?