Biochemistry, Chemistry of Life

Living things are made from chemical compounds, so we must have a basic understanding of chemistry to study biology.

Structure of the Atom Usually, there is an equal number of protons and electrons so an atom is neutral.

What Is An Element? Pure substance consisting of only one type of atom. These are listed on the periodic table

What Is a Compound? A chemical combination of two or more elements For example if two hydrogen molecules are combined with one oxygen molecule what is the resulting compound? .

Atoms in compounds are held together by chemical bonds.

Covalent Bonds are formed when electrons are shared.

Ionic Bonds are formed when electrons are transferred from one atom to another.

The transfer of electrons results in an atom either having a positive charge or a negative charge. These atoms with a charge are called ions.

Review 1.What are the three components of an atom? Protons, neutrons, and electrons 2.Which ones are in the nucleus of the atom? Protons and neutrons 3.Which ones are in the outer shell, and what charge do they have? Electrons (-)

4. What is an ionic bond? A chemical bond between atoms that is formed when one or more electrons are transferred. What is a covalent bond? A chemical bond formed when electrons are shared between atoms.

What Is an Organic Compound? Compounds created within organisms, or living things. Let’s look at the periodic table and do some coloring

Some basic elements make up most organic compounds: Carbon…………….black Hydrogen…………yellow Oxygen…………….red Nitrogen……………blue Phosphorous*……purple Calcium*…………..green *trace amounts

What are 4 Groups of Organic Compounds Found in Living Things? Carbohydrates Lipids Nucleic Acids Proteins

Carbohydrates – main source of energy

Lipids – store energy

Nucleic Acids - contain genetics (DNA and RNA)

Proteins regulate cell processes, build bone and muscle, help fight disease.

Properties of Water Water is the most abundant compound in most living things. Water is a polar molecule!!!!

What is Polarity? A molecule in which the charges are unequally distributed. For example, in the water molecule, the electrons are more attracted to the nucleus of the oxygen atom with 8 protons, than to the nucleus of the hydrogen atom with only 1 proton. This gives water some very unique properties.

Water has a “bent” shape due to Polarity

Acids and Bases Scientists devised a measurement system called the pH scale to indicate the concentration of H+ (hydrogen) ions in a solution. Pure water has a pH of 7, which is neutral. Acids, have higher concentrations of H+ ions, and a pH value below 7, while bases have lower concentrations, and a value above 7.

The pH of fluids in most cells in the human body is between 6. 5 and 7 Controlling proper pH levels is important to homeostasis. Buffers are weak acids or bases that act to regulate pH levels.

Chemical Reactions A process that changes one set of chemicals into another . The elements or compounds that enter into a reaction are called the reactants. The element or compound produced by the reaction is called the product. Reactions always require the breaking and forming of bonds.

Energy Humans need to use energy to grow, think, breathe, and even dream. This release of energy we need, comes from the chemical reactions that occur when we metabolize, or break down food that we eat.

What Are Enzymes? Sometimes chemical reactions occur very slowly, and need a catalyst to speed up the process. Enzymes are proteins that speed up chemical reactions that occur in cells.