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

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 : ..........

Complete the following analogy-type questions:
$(i)$ Cells of cambium between vascular bundles : Intrafascicular cambium :: Cells of medullary rays : .....
$(ii)$ Cambium cells dividing towards the pith : Secondary xylem :: Cambium cells dividing towards the periphery : .......

The function of cork cambium $(phellogen)$ is to produce

In an annual ring,the light coloured part is known as

Vascular cambium of stem is