Our genetic makeup determines our appearance (the colour of our hair and eyes, if we are tall or short) and how we respond to different external factors (nutrients, physical activities, medications). Our DNA can explain how we metabolize certain substances and how our body can lose and gain weight.
The basic unit of our DNA. Each unit consists of a phosphate group, pentose (sugar with five carbons in the ring) and nitrogenous bases. Between individual nucleotides, only the nitrogenous bases differ. In human DNA there are four different nitrogenous bases (Cytosine (C), Guanine (G), Thymine (T) and Adenosine (A)) and, consequently, four different nucleotides.