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JAMB Biology 2012 Question 22

Question 22

Growth and Development

Which of the following is involved in secondary thickening in plants?

  1. A.Collenchyma and xylem cells.
  2. B.Vascular cambium and collenchyma cells.
  3. C.Vascular cambium and cork cambium.
  4. D.Cork cambium and sclerenchyma.
Show the answer and explanation

Answer: C (Vascular cambium and cork cambium.)

Explanation

Secondary thickening comes from two dividing layers: the vascular cambium makes new xylem and phloem, and the cork cambium makes the bark.