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.
Human skin-derived VD3 is produced from 7-dehydroxycholesterol upon exposure to ultraviolet B radiation (UVB, wavelength 290â315 nm). As a fat-soluble vitamin, dietary vitamin D is incorporated into chylomicrons and transported via lymphatics into the venous circulation. Some of the dietary vitamin D is extracted by adipose tissue and muscle, but the remainder and most of the endogenously synthesised vitamin D is transported to the liver.