Konya (Turkish pronunciation: [Ëkon.ja]; Greek: á¼°ÎºÏÎ½Î¹Î¿Î½ IkÃ³nion, Latin: Iconium) is a major city in the Central Anatolia Region of Turkey. It is the seventh-most-populous city in Turkey. As of 2016[update], Konya has a population of over 2.1 million.
Vitamin A is needed by the retina of the eye in the form of retinal, which combines with protein opsin to form rhodopsin, the light-absorbing molecule necessary for both low-light (scotopic vision) and color vision. Retinol, the form of vitamin A absorbed when eating animal food sources, is a yellow, fat-soluble substance. 2  Since the pure alcohol form is unstable, the vitamin is found in tissues in a form of retinyl ester. 3  It is also commercially produced and administered as esters such as retinyl acetate or palmitate.
Sunlight and Vitamin D Synthesis What type of sunlight provides the best vitamin D? 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.