Question

Cambial cells are formed from

• A. Promeristem
• B. Collenchyma
  
• C. Parenchyma
• D. All of the above

Answer 1

The correct option is A Promeristem

• Cambium is composed actively dividing cells which form a layer between xylem and phloem.
  
• It is responsible for the secondary growth in stems and roots (increase in thickness).
  
• It is a single layer of initial cells which are derived from promeristem (actively dividing, undifferentiated cells with thin-wall).
  
• The cambial cells divide to produce the secondary xylem towards the centre of the stem and secondary phloem toward the outside.
  
• The cambium originates from undifferentiated cells that have retained their embryonic capacity for continued growth and differentiation.
  
• So, the correct answer is 'Promeristem'.