Fill in the blanks.
(i) The cambium is generally more active on the A side than on the B.
(ii) In the C season, cambium is very active and produces a large number of xylarly elements having vessels with wider cavities.
(iii) The D wood is lighter in colour and has a lower density.
(iv) The two kinds of woods that appear as alternate concentric rings, constitute an E.
(v) In old trees, the greater part of F xylem is dark brown due to deposition of organic compounds like tannins, resins, oils, gums.
(vi) In old trees, the region comprising dead elements with highly lignified walls and is called G wood.
(vii) The peripheral region of the secondary xylem is lighter in colour and is known as the H wood.
(viii) The I is impervious to water due to suberin deposition on the cell wall.
(ix) J phellem, and K are collectively known as periderm.
(x) L is a non-technical term that refers to all tissues exterior to the vascular cambium. When it is formed early in the season, it is called M or N bark.
(xi) In the dicot root, the vascular cambium is completely O in origin.
(xii) The ground tissue system forms the main bulk of the plant. It is divided into three zones- P, pericycle and Q.
(xiii) The wood is actually a secondary R.