Carbon atoms form four bonds. A single bond can be referred to as a sigma bond. A double bond contains one sigma and one pi bond. A triple bond contains one sigma and two pi bonds.
Ultraviolet radiation can alter the chemical structure of DNA by causing new covalent bonds to form.
When this happens, the affected carbon atoms shift from a sp 2 hybridization state to a sp 3 hydridization state. This changes the chemical sstructure of the DNA and can cause DNA-replicating cell machinery to malfunction and introduce a mutation when trying to copy the damamged DNA strand. Such mutations can lead to skin cancer. Food can be classified as being composed of Carbohydrates, Fats, and Proteins. Carbohydrates can be utalized as energy by our bodies.