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  2. Iron in biology - Wikipedia

    en.wikipedia.org/wiki/Iron_in_biology

    Heme iron in animals is from blood and heme-containing proteins in meat and mitochondria, whereas in plants, heme iron is present in mitochondria in all cells that use oxygen for respiration. Like most mineral nutrients, the majority of the iron absorbed from digested food or supplements is absorbed in the duodenum by enterocytes of the ...

  3. Heme - Wikipedia

    en.wikipedia.org/wiki/Heme

    Binding of oxygen to a heme prosthetic group. Heme (American English), or haem (Commonwealth English, both pronounced /hi:m/ HEEM), is a ring-shaped iron-containing molecular component of hemoglobin, which is necessary to bind oxygen in the bloodstream. It is composed of four pyrrole rings with 2 vinyl and 2 propionic acid side chains. [1]

  4. Trace metal - Wikipedia

    en.wikipedia.org/wiki/Trace_metal

    Roughly 5 grams of iron are present in the human body and is the most abundant trace metal. [1] It is absorbed in the intestine as heme or non-heme iron depending on the food source. Heme iron is derived from the digestion of hemoproteins in meat. [4] Non-heme iron is mainly derived from plants and exist as iron(II) or iron(III) ions. [4]

  5. Cofactor (biochemistry) - Wikipedia

    en.wikipedia.org/wiki/Cofactor_(biochemistry)

    Vitamins can serve as precursors to many organic cofactors (e.g., vitamins B 1, B 2, B 6, B 12, niacin, folic acid) or as coenzymes themselves (e.g., vitamin C). However, vitamins do have other functions in the body. [29] Many organic cofactors also contain a nucleotide, such as the electron carriers NAD and FAD, and coenzyme A, which carries ...

  6. Plant nutrients in soil - Wikipedia

    en.wikipedia.org/wiki/Plant_nutrients_in_soil

    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 ...

  7. Porphyrin - Wikipedia

    en.wikipedia.org/wiki/Porphyrin

    In vertebrates, an essential member of the porphyrin group is heme, which is a component of hemoproteins, whose functions include carrying oxygen in the bloodstream. In plants , an essential porphyrin derivative is chlorophyll , which is involved in light harvesting and electron transfer in photosynthesis .

  8. Iron-binding proteins - Wikipedia

    en.wikipedia.org/wiki/Iron-binding_proteins

    Iron-binding proteins are carrier proteins and metalloproteins that are important in iron metabolism [1] and the immune response. [2] [3] Iron is required for life.Iron-dependent enzymes catalyze a variety of biochemical reactions and can be divided into three broad classes depending on the structure of their active site: non-heme mono-iron, non-heme diiron , or heme centers. [4]

  9. Cytochrome - Wikipedia

    en.wikipedia.org/wiki/Cytochrome

    The iron in cytochromes usually exists in a ferrous (Fe 2+) and a ferric (Fe 3+) state with a ferroxo (Fe 4+) state found in catalytic intermediates. [1] Cytochromes are, thus, capable of performing electron transfer reactions and catalysis by reduction or oxidation of their heme iron. The cellular location of cytochromes depends on their function.