Hydrophytes:
Since all plants require water in order to survive plants usually have special features in order to absorb and retain water to keep the plant alive but because hydrophytes are plants that are in water at all times they do not need to engage in the cycle of water retention like other plants but hydrophytes require numerous special adaptations.Because mineral, CO2 and 2 are less present in water then an equal volume of air, they are able to enter by direct diffusion into the plant, however this is then slower then from air. Because of this the tissues, of both the leaves and stem, tends to have larger airspaces around the cells, particularly in the palisade and spongy mesophyll layer of the plant to facilitate diffusion of substances that are needed and to aid buoyancy. Also hydrophytes that are full submerged have no stomata or waxy cuticle as these are not required as these plants live in water, instead the stomata and the waxy cuticle are found on the floating parts of the leaf to allow efficient gas exchange and to prevent excess water loss on very hot days if the stomata and waxy cuticle are present on submerged leaves they may be dense and therefore effect buoyancy of the leaf sometimes a very thin cuticle is present on submerged leaves this is to then prevent algae but still allows photosynthesis. The stomata in the leaf are open majority of the time because water is abundant and so there is no need for it to be kept or stored in the plant. This also means that the guard cells on the stomata are generally inactive as the stomata is a pore in the plants leaves where the water vapour and other gasses leave and enter the plant, the diffusion of gasses entering and exiting the leaf through the stomata that are needed for photosynthesis and respiration. they are also the main route by which water is lost from the plant. The leaf structure for hydrophytes is an important adaptation in order for the plant to survive. For the leaves of the plant to float on the surface of a pond most aquatic plants have flat leaves which act as a type of flotation device for the plant. Hydrophytes havevery large air spaces around their leaf cells , especially the spongy and palisade (mesophyll) layers , this aids buoyancy in the leaves , so therefore they are closer to the surface for photosynthesis , it also facilitates diffusion of minerals and gases for photosynthesis and respiration. The submerged leaves are often quite divided to create this large surface area for absorption and photosynthesis, photosynthesis is essential in any plant as it converts the solar energy into chemical energy as organic molecules the large surface area of the leaves to capture as much light as possible this is effective therefore the plant as an increase of light intensity exposed to the leaf increases the rate of photosynthesis up to its maximum which means the the plant receives the chemical energy that is needed at an optimum rate. The larger leaves also minimises water resistance hence stopping potential water damage to leaves. Hydrophytes usually have small roots because minerals and gases which are needed for respiration and photosynthesis are dissolved in the surrounding water , or diffused into the small thin leaves that are adapted specifically to allow diffusion , so therefore the roots are only needed for anchorage and stability , for example water caltrop and giant water lilies .
Hydrophytes:Since all plants require water in order to survive plants usually have special features in order to absorb and retain water to keep the plant alive but because hydrophytes are plants that are in water at all times they do not need to engage in the cycle of water retention like other plants but hydrophytes require numerous special adaptations.Because mineral, CO2 and 2 are less present in water then an equal volume of air, they are able to enter by direct diffusion into the plant, however this is then slower then from air. Because of this the tissues, of both the leaves and stem, tends to have larger airspaces around the cells, particularly in the palisade and spongy mesophyll layer of the plant to facilitate diffusion of substances that are needed and to aid buoyancy. Also hydrophytes that are full submerged have no stomata or waxy cuticle as these are not required as these plants live in water, instead the stomata and the waxy cuticle are found on the floating parts of the leaf to allow efficient gas exchange and to prevent excess water loss on very hot days if the stomata and waxy cuticle are present on submerged leaves they may be dense and therefore effect buoyancy of the leaf sometimes a very thin cuticle is present on submerged leaves this is to then prevent algae but still allows photosynthesis. The stomata in the leaf are open majority of the time because water is abundant and so there is no need for it to be kept or stored in the plant. This also means that the guard cells on the stomata are generally inactive as the stomata is a pore in the plants leaves where the water vapour and other gasses leave and enter the plant, the diffusion of gasses entering and exiting the leaf through the stomata that are needed for photosynthesis and respiration. they are also the main route by which water is lost from the plant. The leaf structure for hydrophytes is an important adaptation in order for the plant to survive. For the leaves of the plant to float on the surface of a pond most aquatic plants have flat leaves which act as a type of flotation device for the plant. Hydrophytes havevery large air spaces around their leaf cells , especially the spongy and palisade (mesophyll) layers , this aids buoyancy in the leaves , so therefore they are closer to the surface for photosynthesis , it also facilitates diffusion of minerals and gases for photosynthesis and respiration. The submerged leaves are often quite divided to create this large surface area for absorption and photosynthesis, photosynthesis is essential in any plant as it converts the solar energy into chemical energy as organic molecules the large surface area of the leaves to capture as much light as possible this is effective therefore the plant as an increase of light intensity exposed to the leaf increases the rate of photosynthesis up to its maximum which means the the plant receives the chemical energy that is needed at an optimum rate. The larger leaves also minimises water resistance hence stopping potential water damage to leaves. Hydrophytes usually have small roots because minerals and gases which are needed for respiration and photosynthesis are dissolved in the surrounding water , or diffused into the small thin leaves that are adapted specifically to allow diffusion , so therefore the roots are only needed for anchorage and stability , for example water caltrop and giant water lilies .
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