Chemical Components of Cells - Part I: Sugars 1/14 Living organisms are chemical systems Cells contain relatively few elements The distribution of elements differs dramatically from living organisms to inanimate matter Mostly carbon, nitrogen, oxygen, and hydrogen Why do living organisms contain so much hydrogen and oxygen? Water is the most abundant molecule in the cell Atoms can interact with each other through covalent and non-covalent bonds MOLECULES ARE COVALENTLY BONDED ATOMS Result from the sharing of electrons & form the backbone of molecules Strong molecular bonds that require energy to make and break The number of electrons in the outer shell determine reactivity* Not always shared equally (i.e. Polar vs non-polar molecules)