Biochemistry The chemistry of life.

Structure of an Atom Atoms are made of three subatomic particles. Protons – positively charge particles found in the nucleus of an atom. Neutrons – particles with no charge found in the nucleus of an atom Electrons – negatively charged particles found in clouds, moving around the nucleus of an atom.

The Periodic Table The periodic table is a means of organizing all of the known elements. The are put in order by their Atomic Number (the number of protons they have). Each element also has an Atomic Mass (the number of protons + the number of neutrons) and a symbol that represents the element.

Types of Bonds There are two types of bonds. Ionic Bonds involve the transfer of electrons between atoms. Covalent Bonds involve the sharing of electrons between atoms.

Properties of Water Water has several distinct properties that make it so important to living things. Water can attract other water molecules (cohesion) and water can attract molecules of different substances (adhesion). Water also mixes well with other molecules, creating solutions.

pH Level The pH level of a water based solution is determined by the level of hydrogen ions (H+) in the solution. The pH scale goes from 0 (very acidic) to 14 (very basic), with 7 (the middle point) being neutral (neither acidic nor basic).

Organic Molecules There are six elements that are most common in living things. Those are : Carbon, Hydrogen, Nitrogen, Oxygen, Phosphorous, and Sulfur. They are referred to as: CHNOPS. Of these Carbon is the most common, and most important.

Organic Molecules (cont.) Carbon based molecules are called Organic Molecules, and all living things are made up of organic molecules. There are four major types of organic molecules: Carbohydrates, Proteins, Lipids, and Nucleic Acids.

Carbohydrates These are sugars and are used for energy by living things. Carbohydrates can be simple sugars, like sucrose, or long complicated sugars, like starches. Carbohydrates are found in breads, oats, cereals, pasta and potatoes.

Proteins Proteins are a very important class of organic molecule, because they make up most of the material of living things. There are 7 types of proteins. Among those are structural proteins, contractual proteins, hormones, and enzymes. Enzymes are biological catalysts, that speed up chemical reactions in living things.

Lipids and Nucleic Acids Fats, oils and waxes are all types of lipids. They are used to protect and preserve living organisms. DNA and RNA are the two types of nucleic acids. The carry the genetic information of all organisms.

Chemical Reactions A chemical reaction is the breaking of one set of chemical bonds and the creation of a new set of chemical bonds through the rearrangement of the atoms involved. Reactions involve Reactants (the atoms or molecules going into the reaction) and Products (the atoms or molecules that result from the reaction).