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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 ...
It is a metallo-oxo cluster comprising four manganese ions (in oxidation states ranging from +3 to +4) [6] and one divalent calcium ion. When it oxidizes water, producing oxygen gas and protons, it sequentially delivers the four electrons from water to a tyrosine (D1-Y161) sidechain and then to P680 itself.
Xylem moves water and mineral ions in the plant and phloem accounts for organic molecule transportation. Water potential plays a key role in a plant's nutrient uptake. If the water potential is more negative in the plant than the surrounding soils, the nutrients will move from the region of higher solute concentration—in the soil—to the ...
The oxidation of water is catalyzed in photosystem II by a redox-active structure that contains four manganese ions and a calcium ion; this oxygen-evolving complex binds two water molecules and contains the four oxidizing equivalents that are used to drive the water-oxidizing reaction (Kok's S-state diagrams).
Water stress (drought and salt stress) is one of the major environmental problems causing severe losses in agriculture and in nature. Drought tolerance of plants is mediated by several mechanisms that work together, including stabilizing and protecting the plant from damage caused by desiccation and also controlling how much water plants lose through the stomatal pores during drought.
As a water molecule evaporates from the leaf's surface it pulls on the adjacent water molecule, creating a continuous water flow through the plant. [ 6 ] Two major factors influence the rate of water flow from the soil to the roots: the hydraulic conductivity of the soil and the magnitude of the pressure gradient through the soil.
The Casparian strip prevents mineral nutrient ions from moving passively through the endodermal cell walls. Water and ions move in these cell walls via the apoplast pathway. Ions outside the endodermis must be actively transported across an endodermal cell membrane to enter or exit the endodermis. Once inside the endodermis, the ions are in the ...
It also allows plants to draw water from the root through the xylem to the leaf. Water is constantly lost through transpiration from the leaf. When one water molecule is lost another is pulled along by the processes of cohesion and tension. Transpiration pull, utilizing capillary action and the inherent surface tension of water, is the primary ...