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Vitamin D is a group of fat-soluble secosteroids responsible for increasing intestinal absorption of calcium, magnesium, and phosphate, and for many other biological effects.[1][2][3] In humans, the most important compounds in this group are vitamin D3 (cholecalciferol) and vitamin D2 (ergocalciferol).[2][3][4] The major natural source of ...
Vitamin D deficiency or hypovitaminosis D is a vitamin D level that is below normal. It most commonly occurs in people when they have inadequate exposure to sunlight, particularly sunlight with adequate ultraviolet B rays (UVB).[1][2][3] Vitamin D deficiency can also be caused by inadequate nutritional intake of vitamin D; disorders that limit ...
Ergocalciferol is a secosteroid formed by a photochemical bond breaking of a steroid, specifically, by the action of ultraviolet light (UV-B or UV-C) on ergosterol, a form of provitamin D 2. [19] Like cholecalciferol, ergocalciferol is inactive by itself. It requires two hydroxylations to become active: the first in the liver by CYP2R1 to form ...
Vitamin B6 is one of the B vitamins, and thus an essential nutrient.[1][2][3][4] The term refers to a group of six chemically similar compounds, i.e., "vitamers", which can be interconverted in biological systems. Its active form, pyridoxal 5′-phosphate, serves as a coenzyme in more than 140 enzyme reactions in amino acid, glucose, and lipid ...
Retinoids have many important functions throughout the body including roles in vision, [1] regulation of cell proliferation and differentiation, growth of bone tissue, immune function, and activation of tumor suppressor genes . Research is also being done into their ability to treat skin cancers. Currently, alitretinoin (9- cis -retinoic acid ...
Glucose is a sugar with the molecular formula C 6 H 12 O 6.Glucose is overall the most abundant monosaccharide, a subcategory of carbohydrates.Glucose is mainly made by plants and most algae during photosynthesis from water and carbon dioxide, using energy from sunlight, where it is used to make cellulose in cell walls, the most abundant carbohydrate in the world.
Deoxyribonucleic acid (/ d iː ˈ ɒ k s ɪ ˌ r aɪ b oʊ nj uː ˌ k l iː ɪ k,-ˌ k l eɪ-/ ; DNA) is a polymer composed of two polynucleotide chains that coil around each other to form a double helix.The polymer carries genetic instructions for the development, functioning, growth and reproduction of all known organisms and many viruses. ...
