Question

During the secondary growth in a dicotyledonous stem, the fusiform initials of vascular cambium give rise to

• A. Secondary xylem
• B. Secondary phloem
• C. Medullary ray
• D. Both (a) and (b)

Answer 1

The correct option is D Both (a) and (b)

The cells of vascular cambium are of two types, elongated spindle-shaped fusiform initials, and shorter isodiametric ray initials. Ray initials give rise to vascular rays.

Fusiform initials divide to form secondary phloem on the outer side and secondary xylem on the inner side. With the formation of secondary xylem on the inner side, the vascular cambium moves gradually to the outside by adding new cells.

So, the correct option is 'Both (a) and (b)'.