Question

Choose the correct answers from the alternatives given.
The dark coloured dead wood present in the central region of the old tree is

• A. Spring wood
• B. Heartwood
• C. Sapwood
• D. Cambium

Answer 1

The correct option is B Heartwood

As the tree continues its secondary growth, the greater portion of wood turns dark brown in colour. They turn brown due to progressive filling and deposition of organic compounds like tannins, resins, oils, gums, aromatic substance and essential oils in the vessels and tracheids. This results in their blockage and hence becomes non-functional. Thus its primary function of conduction of water is lost. But due to the depositions, this region becomes hard, durable and resistant to the attack of microbes. Such modified and non-functional wood is called heartwood.

Hence, the correct answer is 'Heartwood'.