In this article we will discuss about the four main types of root stem transition in angiosperms. Type A (Fig. 16.1.1A-1E): This type is represented by Dipsacus, Mirabilis and Fumaria. In the root there are four strands of phloem and four strands of xylem with exarch protoxylem. They are arranged radially. The stem shows four conjoint collateral vascular bundles with [...]
In this article we will discuss about the root stem transition in plants. The change in arrangement of vascular tissues of roots having separate strands of phloem and xylem with exarch protoxylem to collaterally placed phloem and xylem with endarch protoxylem of stem is commonly referred to as root-stem transition. In higher plants root and shoot form a continuous axial [...]
In this article we will discuss about the significance of root stem transition. During vascular transition there is a reorientation of primary xylem and primary phloem. The reorientation of primary vascular tissues commonly takes place in the hypocotyl of the embryo in provascular strands. Transition regions have their own specific orientation of vascular tissues. This orientation cannot be compared with [...]