What is or are true about heart wood?
(A) It does not help in water conduction.
(B) It is also called as alburnum.
(C) It is dark in colour but very soft.
(D) It has tracheary elements which are filled with tannin, resin, etc.
What is or are true about heart wood?
(A) It does not help in water conduction.
(B) It is also called as alburnum.
(C) It is dark in colour but very soft.
(D) It has tracheary elements which are filled with tannin, resin, etc.
The correct option is B Both of (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, the characteristics of the heartwood
are:
A. It represents a 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.
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, the characteristics of the heartwood are:
A. It represents a 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.
