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Plant anatomy or phytotomy is the general term for the study of the internal structure of plants.Originally, it included plant morphology, the description of the physical form and external structure of plants, but since the mid-20th century, plant anatomy has been considered a separate field referring only to internal plant structure.
The epidermis is the outermost cell layer of the primary plant body. In some older works the cells of the leaf epidermis have been regarded as specialized parenchyma cells, [1] but the established modern preference has long been to classify the epidermis as dermal tissue, [2] whereas parenchyma is classified as ground tissue. [3]
A leaf (pl.: leaves) is a principal appendage of the stem of a vascular plant, [1] usually borne laterally above ground and specialized for photosynthesis.Leaves are collectively called foliage, as in "autumn foliage", [2] [3] while the leaves, stem, flower, and fruit collectively form the shoot system. [4]
The first xylem to develop is called 'protoxylem'. In appearance, protoxylem is usually distinguished by narrower vessels formed of smaller cells. Some of these cells have walls that contain thickenings in the form of rings or helices. Functionally, protoxylem can extend: the cells can grow in size and develop while a stem or root is elongating.
It forms a protective covering on the leaf vein and consists of one or more cell layers, usually parenchyma. Loosely-arranged mesophyll cells lie between the bundle sheath and the leaf surface. The Calvin cycle is confined to the chloroplasts of these bundle sheath cells in C 4 plants. C 2 plants also use a variation of this structure. [1]
Cross section of celery stalk, showing vascular bundles, which include both phloem and xylem Detail of the vasculature of a bramble leaf Translocation in vascular plants. Vascular tissue is a complex conducting tissue, formed of more than one cell type, found in vascular plants. The primary components of vascular tissue are the xylem and phloem ...
A hydathode is a type of pore, commonly found in vascular plants, [1] that secretes water through pores in the epidermis or leaf margin, typically at the tip of a marginal tooth or serration. Hydathodes occur in the leaves of submerged aquatic plants such as Ranunculus fluitans [ 2 ] as well as herbaceous plants of drier habitats such as ...
The stem anatomy of ferns is more complicated than that of dicots because fern stems often have one or more leaf gaps in cross section. A leaf gap is where the vascular tissue branches off to a frond. In cross section, the vascular tissue does not form a complete cylinder where a leaf gap occurs.