Metric system. Metric system, international decimal system of weights and measures, based on the metre for length and the kilogram for mass, that was adopted in France in 1795 and is now used officially in almost all countries.
However, if taken in large doses, vitamin D side effects may include: Thirst; Metallic taste in the mouth; Increased urination; Decreased appetite; Weight loss; Constipation; Vomiting; Diarrhea; Itchy skin; Loss of muscle tone; Irritability; Tiredness; Sore eyes; Pain in the bones and joints ...
how is vitamin A involved in perception of light. retinal form of the vitamin combines with protein opsin to form rhodopsin(transforms energy from light into nerve impulse that is sent to the brain. how does vitamin A affect proteins made by a cell. vitamin A enters nucleus, binds to retinoic acid receptor proteins which binds to regulatory part of DNA. this changes mRNA that is made which changes protein that is made.