Organic Compounds and Biochemistry

Monomers & Polymers• Monomer = a small molecule which is a

building block for larger molecules.• Polymers = a long chain molecule that is

made from many monomers bonded together.

• Polymerization = a chemical reaction that joins monomers together to produce a polymer.

Many styrene monomers can be combined to make polystyrene, which is used to make disposable cutlery, CD & DVD cases, packing

materials, insulation, foam drink cups, etc.

Many ethylene monomers can be combined to produce polyethylene, which is used to make many plastic products such as

bags, bottles, containers, wraps, etc.

ethylene polyethylene

polymerization

Dehydration Synthesis

• Joins together 2 monomers with the loss of a water molecule.

Hydrolysis

• Breaks apart a polymer by adding a water molecule at each bond.

• There are 4 classes of biologically important molecules which we will discuss in this course: 1. Carbohydrates2. Lipids3. Nucleic Acids4. Proteins

Biochemistry

Carbohydrates• The main source of energy for most organisms. • Include single sugars as well as small and long

chain polymers of sugar molecules. • Monosaccharides = single unit sugars (i.e. glucose,

fructose, galactose)• Disaccharides = two sugars bonded together (i.e.

sucrose, lactose)• Polysaccharides = long chain of 10 or more sugars

bonded together.

PolysaccharidesCellulose is made from long chains (100’s to 10,000+) of linked glucose sugars. Cellulose plays a structural role in plants and makes up their cell walls. It is also found in cotton, cardboard, and paper products.

PolysaccharidesStarch consists of hundreds of glucose sugars joined together. Starch plays an important role in the human diet and green plants also typically use starch as a means of storing energy.

Lipids• Used by many organisms as a means of

storing energy. • Make up part of the structure of the cell

membrane.• Lipids are not soluble in water. • They include fats, waxes, and sterols.

Nucleic Acids• Carry the cell’s genetic information.• Nucleic acids are made of long chains of

nucleotides.• They are found in all living things. The two

most common are deoxyribonucleic acid (DNA) and ribonucleic acid (RNA).

Nucleotide Structure• Nucleotides are the monomers that form long

chains and make up nucleic acids. • A nucleotide’s structure includes a 5 carbon

sugar, a nitrogenous base, and a phosphate group.

5 Carbon Sugar

Nitrogenous Base

Proteins• Proteins are polymers of amino acids. • The sequence of amino acids needed to make a

protein is encoded in the cell’s genetic code.• Proteins are essential to many cell processes and

have a variety of functions, including:– Serving as enzymes to catalyze reactions.– Playing a structural role as part of the cytoskeleton

that helps to maintain a cell’s shape.– Transmitting or receiving signals in the cell.– Playing roles in the immune system and cell division.