Secondary growth can be defined as a phenomenon where, after the completion of primary tissue formation, more secondary tissues are developed to supplement dermal, vascular and mechanical tissue system in certain plants. The meristem of primary tissue divides. The daughter cells, after differentiation and maturation, form primary tissues of plant body. Primary tissues include epidermis, cortex, primary phloem, primary xylem [...]
Here is a list of twenty-eight types of stems found in plants. 1. Stem of Helianthus Annuus (Sunflower. Family Asteraceae: Internal Structure before Secondary Growth): The transverse section through the internode of stem is more or less circular in outline and exhibits the following arrangement and structure of tissues from periphery towards centre (Figs. 31.1, 31.1A). Epidermis: The outermost layer [...]
In this article we will discuss about the anatomical structure of some dicotyledonous stems that show secondary growth. 1. Anatomy of Bignonia Stem (Fig. 7.4): The following tissue layers are seen in the T.S. of the stem: 1. Epidermis: It is uniseriate and cuticularised. It is wavy in outline. 2. Cortex: It is parenchymatous and bounded internally by a starch [...]