Teens & Depression. â 1 Depression is a serious problem today and one of the nationâs leading killers of teenaged boys when the number of cases of suicide it generates are factored into the equation.
The first organic molecules were probably very simple carbon-based molecules made of few atoms. These molecules then combined with other simple molecules to form more complex molecules. Over many years and probably trillions and trillions of chemical reactions, more complex molecules, and more stable molecules, formed.
The organic molecules found in living things fall into four major classes. Each class of molecule has features that determine its use in living systems. The first class of molecules are called carbohydrates.