Everyone’s favorite- BIOCHEMISTRY/ORGANIC CHEM! Its what you all took this course for, right???

 Chemistry in nature is very different from the chemistry of living organisms  Nature- small molecules react, and only react when they have the activation energy, or the necessary amount of energy to cause the molecules to begin the reaction  Organisms- large molecules are built, broken down, and reconstructed into other large molecules with very little energy needed. WHY??? Why are you doing this to me?

 Naturally existing molecules that are important (existed on Earth WELL before life originated  Water, oxygen, carbon dioxide  Acids/bases Small, but necessary-

 Living organisms able to go through complex reactions that take these small molecules and construct MUCH larger molecules  Example- PHOTOSYNTHESIS  6 CO2 + 6H2O  C6H12O6 + 6O2  In other words, plants take 6 waters and 6 carbon dioxides to make ONE glucose molecule (and are left with some extra oxygen that they excrete) Chemistry of Life

 4 classes of organic molecules  Organic = large, built by living things  Contain C, H, AND O (none of this is possible without C!) 1.Carbohydrates 2.Proteins 3.Lipids 4.Nucleic Acids So what kind of stuff are we talking about?

 Simple and complex carbohydrates  **Serve as SHORT TERM energy storage  Simple = sugars (single ring molecules)  Glucose, fructose, galactose  Complex = many single rings strung together  starch, glycogen  Come from fruits, wheats  Bonds of simple sugars broken down to release chemical energy Carbohydrates

 MANY different functions (coat skin, hair nails, act as chemical messengers, receive signals on cells, mark cells as important, lower activation energy of reactions  Constructed of different combinations of amino acids that bind together in a specific order and shape (amino acid order  shape  function)  Found in meats, cheese Proteins

 Enzymes  Specialized, often fragile, proteins with a special shape that allows them to assist in a chemical reaction  Act by working with substrate(s) to build or break them into product(s)  **shape can be changed by changes in temperature or pH  Gives body fine control over chemical reactions  This is why a stabile body temperature is so important Special proteins

 Fats, oils, and waxes  Serve as LONG-TERM storage of energy  Often act as cell coverings Lipids

 Built from combinations of 4 nucleotide bases (Adenine, Cytosine, Guanine, Thymine, OR A, C, T, G)  Make up genetic code  Indirectly give ribosome instructions on how to built proteins (this will be covered later) Nucleic Acids