FORESTRY
PLANT AND WOOD ANATOMY
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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The cell of vascular cambium
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The cell of cork cambium
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The cell of pro cambium
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The cell of secondary xylem
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The cell of secondary phloem
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Detailed explanation-1: -The function of these cells is to strengthen the central axis of plant organs mechanically against gravity, mechanical disturbances and physical damage (Fig. 1). The sclerenchyma fibres and sclereids have lignified secondary cell walls mainly composed of S-units (Higuchi, 1990).
Detailed explanation-2: -Wood, also called secondary xylem, is a highly specialized vascular tissue characterized by the presence of thick heavily lignified secondary cell walls composed of three main polymers: cellulose, hemicelluloses (e.g. xylan) and lignin.
Detailed explanation-3: -Both lignin and cellulose are found in the rigid cell walls of the xylem cells (those that conduct water) in the primitive plant Selaginella.
Detailed explanation-4: -Xylem is a tissue consisting of dead, hollowed-out cells that form a system of pipes. The walls of xylem cells are lignified (strengthened with a substance called lignin ).