Question

In the primary tissues of the stem, the cambium separating xylem and phloem is called as
A. Procambium
B. Intrafascicular cambium
C. Cork cambium
D. Interfascicular cambium

Answer 1

Hint:This tissue is primary in origin because it is present in between primary xylem and first phloem and springs from embryonic meristems. It essentially belongs to the category of the vascular cambium.

Complete solution: In plants, there is a specialized layer that contains a bundle of typically actively dividing cells, and this layer is called the cambium or cambial ring. It is found between the xylem (wood) and phloem (bast) and is the major factor in bringing about the secondary growth of parts of the plant such as stems and roots (the girth of the plant increases due to the secondary growth). The cambium present within the vascular strand is named intrafascicular cambium. It's present between the first xylem and the first phloem. It is a primary tissue with respect to its origin. Procambium is the primary meristem of a plant that forms the cambium and first vascular tissues. Cork cambium is the tissue found in many vascular plants as a part of the periderm. It is found within the stem and provides rise to cork on its outer surface and a layer of cells containing chlorophyll on its outer.

So, the correct answer is option B. Intrafascicular cambium.

Note: The new strip of cambium which is made from the permanent cells of interfascicular parenchyma is named the interfascicular cambium. It is secondary in origin because it springs from the permanent cells of medullary rays.