PLANT PHYSIOLOGY
TRANSPORT IN PLANT
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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Enable water to move more easily through the xylem.
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Enable mineral salts to move more easily through the xylem.
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Provide mechanical support to the xylem.
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Make the xylem bitter so animals don’t eat it.
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Detailed explanation-1: -The lignin adds compressive strength and stiffness to the plant cell wall and is believed to have played a role in the evolution of terrestrial plants by helping them withstand the compressive forces of gravity. Lignin also waterproofs the cell wall, facilitating the upward transport of water in xylem tissues.
Detailed explanation-2: -Lignin provides mechanical strength and resistance against pathogens, and makes the cell walls impermeable to water, thus enabling the transport of solutes via tracheids in the xylem tissue.
Detailed explanation-3: -As a complex phenolic polymer, lignin enhances plant cell wall rigidity, hydrophobic properties and promotes minerals transport through the vascular bundles in plant [13]. In addition, lignin is an important barrier that protects against pests and pathogens [14].
Detailed explanation-4: -The cell wall of cells making up the xylem contains lignin. This lignin is water resistant and provides mechanical support to the xylem.
Detailed explanation-5: -The walls of xylem cells are lignified (strengthened with a substance called lignin ). This allows the xylem to withstand pressure changes as water moves through the plant.