Question

What is/are true about heart wood?
(A) It does not help in water conduction
(B) It is also called alburnum
(C) It is dark in colour but very soft
(D) It has tracheary elements which are filled with tannin, resin, e.t.c

• A. B, C and D
• B. A and D
• C. B and D
• D. A, B, and C

Answer 1

The correct option is B A and D

As a result of continuous secondary growth in subsequent years, the older part of the secondary xylem or wood becomes non-functional as it looses the power of conduction. The cells of this wood get filled with resins or tannins which are produced by the adjacent functional cells. The non-functional secondary xylem becomes hard and durable. It is blackish in colour and is called heartwood or duramen.

So, characteristics of heartwood are:

A. It represents non-functional part of the secondary xylem and therefore doesn't help in the conduction of water.

B. It is also called duramen.

C. It is dark in colour and is very hard.

D. Tannins, resins, gums are deposited in the tracheary elements.

Hence, in the question, statements A and D are true for heartwood.