"Plant Anatomy". In: Encyclopedia of Life Sciences
Plant Anatomy Introductory article Gregor Barclay, University of the West Indies, St Augustine, Trinidad and Tobago Article Contents . Introduction Plant anatomy describes the structure and organization of the cells, tissues and organs . Meristems of plants in relation to their development and function. Dermal Layers . Ground Tissues Introduction . Vascular Tissues . The Organ System Higher plants differ enormously in their size and appear- . Acknowledgements ance, yet all are constructed of tissues classed as dermal (delineating boundaries created at tissue surfaces), ground (storage, support) or vascular (transport). These are meristems arise in the embryo, the ground meristem, which organized to form three vegetative organs: roots, which produces cortex and pith, and the procambium, which function mainly to provide anchorage, water, and nutri- produces primary vascular tissues. In shoot and root tips, ents;stems, which provide support;and leaves, which apical meristems add length to the plant, and axillary buds produce food for growth. Organs are variously modified to give rise to branches. Intercalary meristems, common in perform functions different from those intended, and grasses, are found at the nodes of stems (where leaves arise) indeed the flowers of angiosperms are merely collections of and in the basal regions of leaves, and cause these organs to leaves highly modified for reproduction. The growth and elongate. All of these are primary meristems, which development of tissues and organs are controlled in part by establish the pattern of primary growth in plants. groups of cells called meristems. This introduction to plant Stems and roots add girth through the activity of anatomy begins with a description of meristems, then vascular cambium and cork cambium, lateral meristems describes the structure and function of the tissues and that arise in secondary growth, a process common in organs, modifications of the organs, and finally describes dicotyledonous plants (Figure 2).
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