AP BIOLOGY

Detailed explanation-1: -The vascular cambium arises between the primary xylem and phloem of a young stem or root. Parenchymatous cells become meristematic and begin to produce secondary xylem or wood toward the inside of the cambium and secondary phloem toward the outside of the cambium.

Detailed explanation-2: -The vascular cambium produces new vascular tissue and is responsible for most of the radial expansion of stems and roots. In a cross section of a stem or root the vascular cambium exists as a circle of cells, only a few cells in width. In three dimensions the vascular cambium is a cylinder.

Detailed explanation-3: -With the onset of the secondary growth, fascicular cambia are interconnected with interfascicular cambia located between the vascular bundles, forming a complete vascular cambium in woody stems (Figure 1). The interfascicular cambia are known to originate from the parenchymatic cells in the interfascicular region.

Detailed explanation-4: -Secondary phloem and xylem tissues are produced through the activity of vascular cambium, the cylindrical secondary meristem which arises among the primary plant tissues. Most dicotyledonous species undergo secondary development, among them Arabidopsis.

Detailed explanation-5: -Vascular cambium and cork cambium, also called secondary meristem, are responsible for secondary growth in plants. They increase the thickness of the plant body.