Chemical Basis of Life (1) Biology is the study of living organisms. In turn, organisms are chemical machines, i.e. organisms are composed of molecules, which are collections of smaller units called atoms. Therefore, we need to consider the chemistry of life or biochemistry. Chemical Bonding -electrons occupy various positions (distances) from the nucleus of an atom, known as energy levels. -as an electron moves further from the nucleus of an atom, its potential energy increases. …showed first 75 words of 656 total…

…showed last 75 words of 656 total…covalent bonds. -Even though covalent bonds may be polar or non-polar, whether the molecule as a whole is polar is polar depends upon bond polarity and molecule shape. -E.g. carbon tetrachloride (CCl4) has a symmetrical shape and is non-polar (even though it consists of polar covalent bonds) methanol (CH3OH) has polar covalent bonds and it is asymmetrical in shape. ** This concept of polar molecules is extremely important because WATER is a polar molecule.