In this article we will discuss about the stages of secondary growth in dicotyledonous root with the help of suitable diagrams. The roots of some herbaceous dicotyledons and of all gymnosperms and woody dicotyledons show secondary growth in thickness. The tissues of secondary origin in the dicotyledonous roots are basically similar to those of the stem, but the way of [...]
In this article we will discuss about the secondary growth in certain dicotyledonous stem:- 1. Aristolochia 2. Cucurbita. Dicotyledonous Stem # 1. Aristolochia: Aristolochia is a liane (woody climber) and its secondary growth in stem differs from the normal woody plants. The most striking differences are the formation of only parenchymatous medullary rays by the interfascicular cambium, and vascular tissues [...]
In this article we will discuss about the transverse sections of petiole of some flowers:- 1. Cucurbita 2. Sunflower 3. Piper Betle 4. Waterlily. 1. Cucurbita: A transverse section through the petiole of Cucurbita shows the following anatomical features (Fig. 5.124): It is wavy in outline having distinct ridges and furrows and a large cavity at the centre. (i) Epidermis: [...]