Which of the following statements about plant cell walls is true?
(a) The microtubule cytoskeleton directs the orientation in which cellulose is deposited in the cell wall.
(b) The molecular components of the cell wall are the same in all plant tissues.
(c) Because plant cell walls are rigid, they are not deposited until the cell has stopped growing.
(d) The cellulose found in cell walls is produced as a precursor molecule in the cell and delivered to the extracellular space by exocytosis.
Choice (a) is correct. Different plant cells can have specially adapted types of walls [choice (b)]. Most newly formed plant cells have a primary cell wall that is thin and can expand to accommodate cell growth [choice (c)]. Cellulose is synthesized on the outer surface of the cell [choice (d)].
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example of __________.
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What will be an ideal response?
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