<span>Vitamin D.
Vitamin D is made from 7-dehydrocholesterol and needs UV light in order to be activated. Because the children are not exposed to sunlight, they are receiving insufficient UV light.</span>
All photosynthetic organisms <span />
The initiation of DNA replication occurs in two steps. First, a so-called initiator protein unwinds a short stretch of the DNA double helix. Then, a protein known as helicase attaches to and breaks apart the hydrogen bonds between the bases on the DNA strands, thereby pulling apart the two strands.
So yeah xD
~ Hope this helps! -by Kana ^^