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The heartwood occupies:

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The central or innermost layers of the stem and has deposition of organic compounds like tannins, resins, oils, gums, aromatic substances and essential oils

The peripheral region of the secondary xylem and has deposition of organic compounds like tannins, resins, oils, gums, aromatic substances and essential oils

The central or innermost layers of the stem and is involved in the conduction of water and minerals from root to leaf

The peripheral region of the secondary xylem and is involved in the conduction of water and minerals from root to leaf

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detailed solution

Correct option is A

In very old trees, the greater part of secondary xylem is dark brown due to deposition of organic compounds like tannins, resins, oils, gums, aromatic substances and essential oils in the central or innermost layers of the stem. These substances make it hard, durable and resistant to the attacks of microorganisms and insects. This region comprises dead elements with highly lignified walls and is called heartwood. The heartwood does not conduct water but it gives mechanical support to the stem.

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