Minerals are classified as essential if they meet the following properties:
The Nothing, a plant would not be able to complete its life cycle
The function of the element can not be supported by another
O element is directly involved in the metabolism of the plant
Nutrients minerals are used for a variety of purposes, including:
The tissue components, such as protein synthesis
Cellular control
Enzyme components
electron transfer
Metabolic processes
regulatory control systems.
Apoplastic transport is through the cell walls interconnected through the root of the plant - the major route of absorption of nutrients.
The apoplast is the plant cell walls and intercellular spaces. The symplast cells are connected by plasmodesmata living. Before the ions reach the stretch mark Caspary, transportation is apoplastic nonselective cation to be more readily absorbed due to the negatively charged cell walls.
Ions to enter the stele (pericycle + xylem + phloem) with transport apoplastic, they must pass through the membranes. Parts of selective membranes are transport proteins.
Ions are also taken by the selective symplastic transport system, again via transport proteins in the membrane.
As the ions are increasingly entering the xylem cells by active transport, water follows by osmosis (for passive transport). Transport proteins are proton pumps.
If the concentration of ions in the soil the plant is greater than that obtainable by facilitated diffusion, a passive process. This membrane potential causes cations to enter the cell, e.g., K + ions through potassium channel proteins. Symporter protein chains accept anions to be transported into the cell.
Once the nutrients are in the xylem, they are transported to other cells, such as leaves, by transpiration cohesion-tension mechanism:
When sweat stomata of the leaf water, a strain occurs in the sheet, pulling nutrients in leaf veins in the apoplastic cells. The tension pulls the xylem nutrients in the veins of the leaves. This in turn pulls the nutrients xylem of the stem, which attracts the nutrients to move outwardly and upwardly. The movement of water and nutrients is assisted by the force of cohesion of the water molecules bond together by hydrogen bonding of water molecules.
Nutrient absorption is regulated by various plants / environmental factors:
PH. The soil more acidic, nutrients are less available to the plant, in addition to iron. The lower the pH, specific ions are not available, for example, Cu, Zn, Mn, Fe, Ca, Mg, N. O more plants prefer a pH of about 6.5.
Plants have a negative feedback mechanism that regulates the absorption of nutrients. If the plant has enough of a particular nutrient, the mechanism also prevents the absorption of nutrients.
The nutrients demand for food allows a plant to get the optimal nutrient soil. For example plant roots breathe across several exoenzymes and mucilage, which makes the available evidence.
The geometry of the root, such as the size, the root growth rate, the thickness of the root, root branching and root hairs availability and the impact absorption rate of nutrients.
Conclusions:
Elementary ions are absorbed by plants in solution form. The nutrients it needs regulation through a selection process. People (ions) move to the platform (membranes) pending (xylem system) train The train transports people for all local (tissue) in this line in particular.
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