Question
Heartwood differs from sapwood in
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Presence of rays and fibres
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the absence of vessels and parenchyma
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having dead and non-conducting elements
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being susceptible to pests and pathogens
Solution
C.
having dead and non-conducting elements
As a result of continued secondary growth in subsequent years, the older part of secondary xylem or wood becomes non - functional as it loses the power of conduction. The cells of this wood are filled with resins or tennis produced by adjacent functional, secondary xylem becomes hard, durable and blackish in colour, called heartwood, Now, the function of secondary xylem( water and mineral conduction from roots) is performed by outer younger-rings of xylem, which is called sapwood.
