Hydrophytes generally rely on water for support and structure, thus meaning that supporting tissues like sclerenchyma are reduced or absent in the stem, because this would make the plant more stiff and rigid therefore making it more likely for breakage by water current. Vascular tissues are poorly developed because they are not required for support in submerged plants (if there are xylem, they are found at the centre of the stem so that there is still flexibility), the xylem and phloem vessels are not required for transporting water and nutrients around the plant because the can be easily transported via diffusion and osmosis. There is also little or no lignin in the vascular tissues because further strengthening is not required. The stems are spongy, long, and flexible so that when water moves it flows with it.
Mesophytic plant's stems are strengthened with lignin to prevent bending and broken stems. Therefore this means that while supporting tissues such as sclerenchyma that are reduced or absent in hydrophytic plants, they are present in mesophytic plants because they require extra strengthening to withstand storms, high winds and other wind conditions. Mesophytic plants have a well developed vascular system because they are required both for support in the stem and for the transportation of nutrients and water around the plant. Mesophytic plants rely on water for cell turgidity because it plays a huge role in keeping the plant from wilting (strengthens the stem).
Xerophytes tend to hold large amounts of water in the stems (succulents) e.g. the barrel cacti has no leaves and stores large amounts of water with its stem doing photosynthesis. Xerophytic plants tend to have large, thick stems both for the storage of water and so that the plant can remain upright as the fleshy stem provides the support for the plant to
stay upright (prevents wilting). Xerophytes have well developed xylem and phloem tissues as they rely on these for the transportation of water, minerals and nutrients around the plant's cells, water moving through the xylem also helps to keep the plant cool.
Mesophytic plant's stems are strengthened with lignin to prevent bending and broken stems. Therefore this means that while supporting tissues such as sclerenchyma that are reduced or absent in hydrophytic plants, they are present in mesophytic plants because they require extra strengthening to withstand storms, high winds and other wind conditions. Mesophytic plants have a well developed vascular system because they are required both for support in the stem and for the transportation of nutrients and water around the plant. Mesophytic plants rely on water for cell turgidity because it plays a huge role in keeping the plant from wilting (strengthens the stem).
Xerophytes tend to hold large amounts of water in the stems (succulents) e.g. the barrel cacti has no leaves and stores large amounts of water with its stem doing photosynthesis. Xerophytic plants tend to have large, thick stems both for the storage of water and so that the plant can remain upright as the fleshy stem provides the support for the plant to
stay upright (prevents wilting). Xerophytes have well developed xylem and phloem tissues as they rely on these for the transportation of water, minerals and nutrients around the plant's cells, water moving through the xylem also helps to keep the plant cool.
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