histology of stem

Plant Histology..

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. It has four cellular elements tracheids, tracheae, fibres and parenchyma of which only xylem parenchyma is living. Xylem tracheae (or vessels) are the most active water conducting elements. Based on the pattern of lignification, they can be distinguished into annular, spiral, scalariform, reticul..

They are found irregularly scattered in the ground tissue. Towards the periphery, the bundles are smaller in size while towards the centre, they are larger in size. The smaller bundles are younger, while the larger ones are older. Hence, the arrangement is described as centrifugal. Each vascular b..

It is the main tissue in the plant body, occurring in almost all regions. It is particularly abundant in the root and stem. It is the least specialised among the permanent tissues. The cells of the tissues are called parenchyma cells. These cells are usually spherical or oval in shape. So..

Dracena, Yucca. The concentric bundles are characteristic features of some monocot plants...

. The process that involves the formation of the secondary wall is known as lignification. Due to lignification, the cells lose their living characters at maturity. Hence, in the sclerenchyma cells cytoplasm, nucleus and cell organelles are absent at maturity. The vacuole is represented by an empty..