The angiosperms are characterized by vessels in wood, and therefore, vessel elements were selected to study them in climber species. Xylem is the specialized tissue that transports water and nutrients from the plant–soil interface to stem and leaves and provides mechanical support and storage. Water is the primary solvent for plant nutrition and metabolism and is essential for photosynthesis, turgor and for transport of minerals, hormones and other molecules. Studies on vessels showed that the characters of vessels can throw some light on the phylogeny of species. The short vessel members with many perforation plates with a single large perforation are most specialized and those that were long with elongate obliquely placed perforation plates with many perforations separated by bars that together give a scalariform appearance are primitive. The degree of specialization of vessel elements can be measured in terms of vessel length, breadth and the number of bars on the end plate of vessels. Vessels show highly evolved and primitive vessel elements. Mostly elongated vessel elements are present in middle region of the stem. During this study the broadest vessels were found in the middle part of the stem of dicots (Clitoria, Daemia and Aristolochia) and root of the monocots (Gloriosa) and the narrowest vessel elements were found in different parts of the species investigated. The present work is supported with line drawings of prepared stained sections, provides a framework of the vessels. This study will be very useful to a wideseries of community, who work with plants.
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