Calcium macroelement

Pesticides may change the soil s element content. Some pesticides may increase plants micro- and macroelement content, such as nitrogen, phosphorus, calcium, potassium, magnesium, manganese, iron, copper, barium, aluminum, strontium and zinc, whereas others decrease these or other elements. Pesticides may cause ammoniac compounds to accumulate in the soil. Dimethoate and fluometuron increase nitrates in the soil, while DDT, carbaryl and HCH sharply decrease them. When prometrin was used, soil nitrate content decreased by 30-40% [3]. 

The elements essential for life can be divided into macroelements (daily requirement > 100 mg) and microelements (daily requirement < 100 mg). The macroelements include the electrolytes sodium (Na), potassium (K), calcium (Ca), and magnesium (Mg), and the nonmetals chlorine (Cl), phosphorus (P), sulfur (S), and iodine (I). 

The last column in the table lists some of the functions of minerals. It should be noted that almost all of the macroelements in the body function either as nutrients or electrolytes. Iodine (as a result of its incorporation into iodothyronines) and calcium act as signaling substances. Most trace elements are cofactors for proteins, especially for enzymes. Particularly important in quantitative terms are the iron proteins hemoglobin, myoglobin, and the cytochromes (see p. 286), as well as more than 300 different zinc proteins. 

Morama is a good source of macroelements such as potassium, phosphate, magnesium, and calcium as well as the trace elements zinc, iron, and copper (Amarteifio and Moholo, 1998 Holse et al., 2010 Wehmeyer et al., 1969), as summarized in Table 5.5. 

BIOGEOCHEMICAL CYCLING OE MACROELEMENTS Table 31. Major fluxes of global calcium cycle. 

Six nonmetallic major bioelements or macroelements are needed to form the multitude of macromolecules in a living cell (C, O, H, N, P, S), and four additional metals to neutralize the predominantly negative charges of these macromolecules (K, Mg, Ca, Na). While the elements from carbon to calcium are undisputed major bioelements, some authors may remove sodium (Na) from this list and insert iron (Fe) instead. However, iron - like most trace elements - is a transition element, whereas sodium is an element of a major group of the periodic system like the other three metallic major bioelements. 

Table 1 Water, macroelement (calcium, magnesium, phosphorus, potassium, and sodium) and oligoelement (iron, zinc, copper, manganese, and selenium) content in some foods...

Among the 50 known minerals, between 15 and 20 minerals are natural components of foods that are part of at least one vital biological system of a plant or animal. Some of them are denominated macroelements because of their abundance in foods these include calcium, phosphorus, sodium, potassium, magnesium, and chlorine. Others are called oligoel-ements or trace elements due to their minimal concentration among these are iron, iodine, zinc, copper, chromium, manganese, molybdenum, fluoride, and selenium. 

The catabolites of phytase activity in wheat are myo-inositol, phosphate, and the macroelements potassium, magnesium and calcium. Myo-inositol phosphate ester intermediates with fewer than six phosphate groups do not accumulate within the grain during hydrolysis of the phytin molecule [94], which is indicative of its rapid and complete breakdown by phytases. Movement of the catabolites from the aleurone layer and their redistribution into the developing seedling appears to be by simple diffusion through the endosperm, without any apparent competition for uptake by the scutellum. 

Majority mineral elements Or quantity elements, formerly referred to as macroelements, which occur in food in larger amounts, usually in hundredths to units of weight per cent (hundreds to ten thousands mg/kg) and include alkali metals sodium (Na) and potassium (K), alkaline earth metals magnesium (Mg) and calcium (Ca), halogen chlorine (Cl) and non-metals phosphorus (P) and sulfur (S). 

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