Vitamin d sources clipart

The major natural source of the vitamin is synthesis of cholecalciferol in the skin from cholesterol through a chemical reaction that is dependent on sun exposure (specifically UVB radiation). Cholecalciferol and ergocalciferol can be ingested from the diet and from supplements. Only a few foods, such as the flesh of fatty fish, contain significant amounts of vitamin D, and fish does not contain...

Black and white objects clipart

Most early forms of motion pictures or film were black and white. Some color film processes, including hand coloring were experimented with, and in limited use, from the earliest days of motion pictures. The switch from most films being in black-and-white to most being in color was gradual, taking place from the 1930s to the 1960s. Even when most film studios had the capability to make color...
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