● The`color{violet}(" transverse section")` of a typical `color{violet}("young dicotyledonous stem")` shows that the `color{brown}("epidermis")` is the outermost protective layer of the `color{violet}("stem.")`

● Covered with a thin layer of cuticle, it may `color{violet}("bear trichomes")` and a `color{violet}("few stomata.")`

● The `color{violet}("cells")` arranged in multiple layers between `color{violet}("epidermis")` and `color{violet}("pericycle constitute")` the cortex.

● It consists of `color{violet}("three sub-zones.")`

● The outer `color{brown}("hypodermis,")` consists of a few layers of `color{violet}("collenchymatous cells")` just below the epidermis, which provide mechanical strength to the `color{violet}("young stem. ")`

● `color{brown}("Cortical layers")` below `color{violet}("hypodermis")` consist of rounded `color{violet}("thin walled parenchymatous cells")` with conspicuous intercellular spaces.

● The innermost layer of the `color{violet}("cortex")` is called the `color{brown}("endodermis.")`

● The `color{violet}("cells of the endodermis")` are rich in `color{violet}("starch grains")` and the layer is also referred to as the `color{brown}("starch sheath.")`

● `color{brown}("Pericycle")` is present on the inner side of the `color{violet}("endodermis")` and above the `color{violet}("phloem")` in the form of semi-lunar patches of `color{violet}("sclerenchyma.")`

● In between the `color{violet}("vascular bundles")` there are a few layers of radially placed `color{violet}("parenchymatous cells,")` which constitute medullary rays.

● A large number of `color{brown}("vascular bundles")` are arranged in a ring ; the ‘ring’ arrangement of `color{violet}("vascular bundles ")` is a characteristic of `color{violet}("dicot stem.")`

● Each `color{violet}("vascular bundle")` is `color{violet}("conjoint,")` open, and with `color{violet}("endarch protoxylem.")`

● A large number of rounded, `color{violet}("parenchymatous cells")` with large intercellular spaces which occupy the central portion of the `color{violet}("stem constitute")` the `color{brown}("pith.")`

● The `color{violet}("monocot stem")` has a `color{violet}("sclerenchymatous hypodermis,")` a large number of `color{violet}("scattered vascular bundles,")` each surrounded by a `color{violet}("sclerenchymatous bundle sheath,")` and a large, conspicuous `color{violet}("parenchymatous ground tissue.")`

● `color{violet}("Vascular bundles")` are `color{brown}("conjoint")` and `color{brown}("closed.")`

● Peripheral `color{violet}("vascular bundles")` are generally smaller than the centrally located ones.

● The `color{violet}("phloem parenchyma")` is absent, and `color{violet}("water-containing cavities")` are present within the `color{violet}("vascular bundles.")`