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Nutrients in the soil are taken up by the plant through its roots, and in particular its root hairs.To be taken up by a plant, a nutrient element must be located near the root surface; however, the supply of nutrients in contact with the root is rapidly depleted within a distance of ca. 2 mm. [14] There are three basic mechanisms whereby nutrient ions dissolved in the soil solution are brought ...
Photosystem II (of cyanobacteria and green plants) is composed of around 20 subunits (depending on the organism) as well as other accessory, light-harvesting proteins. Each photosystem II contains at least 99 cofactors: 35 chlorophyll a, 12 beta-carotene, two pheophytin, two plastoquinone, two heme, one bicarbonate, 20 lipids, the Mn 4 CaO
The source of electrons for photosynthesis in green plants and cyanobacteria is water. Two water molecules are oxidized by the energy of four successive charge-separation reactions of photosystem II to yield a molecule of diatomic oxygen and four hydrogen ions.
Plant nutrition is the study of the chemical elements and compounds necessary for plant growth and reproduction, plant metabolism and their external supply. In its absence the plant is unable to complete a normal life cycle, or that the element is part of some essential plant constituent or metabolite .
Has no known biological role, but a variety of plants concentrate it from the soil, and it has a variety of uses in medicine. [11] Some compounds are toxic. In humans, barium ion affects the nervous system. [16] beryllium: 4: 2c: Has no known biological role, but has medical use in certain dental alloys [17] Toxic to humans, esp. via inhalation.
This is why people feel the air is fresh and clean after rain. It is not only because the rain increases the humidity of the air, but more importantly, the concentration of negative ions in the air has increased significantly. [16] Plants tip discharge : The tip of the leaves of vegetation will discharge under the action of the photoelectric ...
Potassium is the main intracellular ion for all types of cells, while having a major role in maintenance of fluid and electrolyte balance. [1] [2] Potassium is necessary for the function of all living cells and is thus present in all plant and animal tissues. It is found in especially high concentrations within plant cells, and in a mixed diet ...
Na + – sodium ions have a similar role to potassium ions. (See Sodium deficiency.) Mn 2+ - manganese ions are seen being used as stabilizer for varying protein configurations. However, manganese ion overexposure is linked to several neurodegenerative diseases such as Parkinson's disease. [3] Mg 2+ – magnesium ions are a component of ...