Importance_of_Water_and_Inorganic_Ions_in_Plants

Explain the Importance of water and inorganic ions (nitrate, calcium and magnesium) to plants Water Cellular activities within the plant require water to occur. Water regulates the temperature of the plant, both internally and externally. Water evaporating from the surface of a plant leaf takes heat away, preventing temperatures from rising too high. Helps the plant and its cells to maintain their structure, by regulating their turgor pressure. Most plant cells have a vacuole that pushes out when water it is filled with water. When plants do not have enough water, they wilt as the cells become flaccid. Water is needed for photosynthesis, where the plant uses the sun’s energy to convert it into food. Hydrogen from water is required for photosynthesis, and sugars produced are carried back around the vascular system of the plant by water. The apoplast, the spaces between cells, contain water, which accumulate there. Nitrates Nitrogen is a very important element in itself. It is needed in both plants and animals for growth and reproduction. Nitrate is a natural material in soils, and 90 percent of the nitrogen that the plant absorbs is in the form of nitrates. Healthy plants typically contain around 3-4% nitrogen in their aboveground. Nitrogen is taken in by plants throughout their lives and there is a correlation between the growth of the plant and the amount of nitrate that it needs. Nitrates can be found in: Chemical fertilizer, Soil organic matter, Animal manure, Treated urban organic wastes. Nitrates are soluble in water and they are transported within the soil by the movement of soil moisture. They are transported around the plant after being taken up by the roots to places where they are needed. Nitrate ions are important in a plant as they are used to make the amino acids in a plant, the building blocks of proteins. Essential plant enzymes are also made and nitrogen is contained in all enzymes essential for all plant functions. Nitrogen is also an important component of several important structural, genetic and metabolic compounds within the plant and nitrates are needed to supply it. It is also a significant component of DNA, the genetic material which allows the plant to reproduce. Plants which are nitrogen-deficient are small in general and develops slowly, as growth is stunted due to the lack of nitrogen necessary to produce the genetic and structural materials for growth. The plant itself will is usually a pale green or yellowish colour, a symptom of nitrogen deficiency, as the plant is lacking in chlorophyll. Leaves will gradually become necrotic and will die, as the plant tries to conserve its available reserves of nitrogen for other more important parts of the plant. Calcium Calcium is another inorganic ion which is essential for living organisms. The movement of the Ca2+ ion in cells functions as a signal, triggering many different cellular processes. In plants, Calcium ions make up one of the essential components of the cell walls and membranes of plant cells. As it has a charge of 2+, it is used to balance the charges of organic anions, usually within the vacuole of the plant cell. It is also found in the middle lamella of plant cells. There, the calcium ions combine with pectin, a structural heteropolysaccharide found in plants where it helps to bind cells together. The calcium in plants is bonded with the pectin, forming calcium pectinate, the substance which holds plant cells together. Calcium ions in the cytosol of plant cells also help in cell signaling and the permeability of the membranes within the plant. Calcium is transported within the plant by water after being taken up by the roots form the soil. Calcium deficiency is common for plants growing on acidic soils, or areas where there is a shortage of water, leading to the slower transportation of the calcium ion. Symptoms of calcium deficiency are the curling of the young leaves or shoots of the plant, as well as poor plant growth. The leaves of the plant are normally yellow and crinkly, and after a while, wilt starting from the tip. Calcium deficiency can be treated as long as it is done quickly. Lime is added to acidic soils to regulate the pH, and organic matter is also added to improve the ability of the soil to retain moisture. Magnesium Magnesium is needed in plants for: Photosynthesis- Magnesium ions is the central element in the production of the green pigment chlorophyll, an essential component of a plant needed to produce food. Carries Phosphorus around the plant, another important molecule which is involved in helping important energy transfers within the cells. Synthesis of sugars, Starch transportation within the plant Activation of enzymes as well as being a constituent of a large number of enzymes within the plant. Needed for the synthesis of nucleic acids. If a plant is lacking in magnesium the older and lower of the leaves will have signs of chlorosis(the general yellowing of leaf tissue). Growth is stunted and any fruits produced are generally small and woody.