THE STEM IS THE MAIN SUPPORTIVE PART OF A PLANT. that grow above the ground .Stem bear leaves (organs of photosynthesis ), which grow at nodes,buds (shots covered by protective scales), which grow at the stem tip.9apical or terminal buds) and in the angle between a leaf and a stem (axillary and lateral buds);and flowers (reproductive structures).The stem forms part of plant's transport system :xylem tissue in the stem transports water and minerals from the roots to the aerial part of the plant , and phloem tissue transport nutrients manufactured in the leaves to other part of the plant . Stem tissues are also used to store water and food . Herbaceous (non woody ) stems have an outer protective epidermis covering a cortex that consist mainly of parenchyma (packing tissue) but also has some collenchyma (strengthening tissue).Woody stems have an outer protective layer of tough bark , which is perforated with lenticels (pores) to allow gas exchange .Inside the bark is a ring of secondary phloem , which surrounds an inner core of secondary xylem.
While surfing the Web, these commands could help you and are absolutely worth learning. By making repetitive motions faster, web surfing becomes so easy and pleasant! The following shortcuts can be work with desktop versions of Chrome, Firefox, and IE. CTRL-T to launch a new browser tab page. Tabbed pages are very useful: they let you open multiple web pages simultaneously without the same memory load as a full browser window. Simply press CTRL-T to launch a new tab. Related: use CTRL-Page Up and CTRL-Page Down to navigate between the tabs. CTRL-Enter to type 'www.' and '.com' Once you ...
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