The narrow layer of thin-walled cells found in dicots (between the phloem and xylem) is known as ..........

Which tissue gives rise to secondary growth?

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

Explain the difference between heartwood and sapwood.

Grafting is attempted in those plants which show:

Complete the following analogy-type questions:
$(i)$ Wood formed during spring season : Early wood :: Wood formed during winter season : .........
$(ii)$ Bark formed early in the season : Early bark :: Bark formed at the end of the season : ..........