STRUCTURAL ORGANISTION OF PLANTS AND ANIMALS
ANATOMY OF FLOWERING PLANTS
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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Presence of tyloses
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Presence of tannins, resins, oils, gums etc.
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Its commercial importance for timber
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Active in water conduction
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Detailed explanation-1: -heartwood, also called duramen, dead, central wood of trees. Its cells usually contain tannins or other substances that make it dark in colour and sometimes aromatic. Heartwood is mechanically strong, resistant to decay, and less easily penetrated by wood-preservative chemicals than other types of wood.
Detailed explanation-2: -(i) It does not help in water and mineral conduction. (ii) It is dark colored but soft. (iii) It has tracheary elements filled with tannins, resins, gums, oil, etc.
Detailed explanation-3: -Hardwood provides mechanical support and does not conduct water.
Detailed explanation-4: -i) It does not help in water conduction. ii) It is also called alburnum. iii) It is light in colour and is very soft. iv) It has tracheary elements which are filled with tannins, resins, etc.