There are 249 calories in a 3.5 oz serving of Ground beef Ground Beef, crumbled, cooked, drained, rinsed. Calorie breakdown: 57% fat, 0% carbs, 43% protein.here are 249 calories in a 3.5 oz serving of Ground beef Ground Beef, crumbled, cooked, drained, rinsed. Calorie breakdown: 57% fat, 0% carbs, 43% protein.
Sunlight and Vitamin D Synthesis. Exposure to the sunâs ultraviolet (UV) rays is required for vitamin D3 (cholecalciferol) to be produced. Vitamin D3 is synthesized in the skin once your unprotected skin receives exposure to sunlights UV rays. The sun emits three different types of radiation, UVA, UVB and UVC. The ozone layer is good at blocking all of the UVC radiation and most of the UVB, however, none of the UVA radiation.
Vitamin D: An Overview. Vitamin D is a fat-soluble vitamin that is metabolized by the body by either sun (ultraviolet light) exposure or dietary intake. There are 2 molecules that make up vitamin D: ergocalciferol (D2) and cholecalciferol (D3). Ultraviolet B (UVB) radiation is absorbed by the skin and converts 7-dehydtocholesterol to vitamin D3. Vitamin D3 then goes into the capillary bed, where it binds to vitamin D binding protein (DBP).