Question

A narrow layer of thin walled cells found between phloem/bark and wood of a dicot stem is

• A. Cork cambium
• B. Vascular cambium
• C. Endodermis
• D. Pericycle

Answer 1

The correct option is B Vascular cambium

The vascular cambium is located between the xylem and the phloem in the stem and root of a vascular plant, and is the source of both the secondary xylem growth (inwards, towards the pith) and the secondary phloem growth (outwards). It is a cylinder of unspecialized meristem cells that divide to give new cells which then specialize to form secondary vascular tissues. Vascular cambia are found in dicots and gymnosperms but not monocots, which usually lack secondary growth. A few leaf types also have a vascular cambium. The vascular cambium usually consists of two types of cells - fusiform initials (tall cells, axially oriented) and ray initials (almost isodiametric cells - smaller and round to angular in shape).

Thus, the correct answer is option B.