The chemicals that make things living! Organic Chemistry The chemicals that make things living!

Organic and Inorganic Inorganic – Molecules or compounds that are not from a living thing Organic – Molecules or compounds that are typically found in living things (these contain a hydrogen bonded to a carbon) Organic compounds always have carbon and hydrogen, but typically have nitrogen and oxygen as well. These four elements (carbon, hydrogen ,oxygen, and nitrogen) are the most abundant elements found in living things

Organic Molecules Which of the following compounds are organic? Water (H2O) Glucose (C6H12O6) Carbon Dioxide (CO2) Oxygen (O2) Urea (CH4N2O) Salt (NaCl) How did you determine this?

Water Water is not organic (because it doesn’t contain carbon) Water is essential to living things because of its properties and the fact that all living things rely on water to survive Water has special properties Polarity – one end of water is more negative and the opposite end more positive Cohesion – the polarity causes water molecules to stick together (negative is attracted to positive ends) Solvent – other substance dissolve easily in water Water can separate to form ions (charged particles) It will form H+ and OH-

pH Ion formation of water is important to pH because pH is a measure of the H+ ions in a solution. Water has a pH of 7 (not acid, not base) because it has an even amount of H+ and OH- ions Acids have a lower pH because they have more H+ ions Bases have a higher pH because they have less H+ ions Buffers are solutions that can neutralize strong acids and bases preventing sudden changes in pH (usually salts)

NaOH + HCl  H2O (water) + NaCl (salt) Neutralization When we mix an acid and a base we get salt and water . . . NaOH + HCl  H2O (water) + NaCl (salt) Our bodies want to maintain a neutral environment (homeostasis), our bodies create buffers Buffers are weak acids and bases that we can secrete to maintain our pH

4 Organic Molecule Types Carbohydrates Sugars (anything sweet) Grains (pasta, bread, rice, cereal, etc.) Lipids Fats (oil, butter, grease, etc.) Proteins Meats (fish, eggs, steak, beans, etc.) Nucleic Acids DNA (found in every living cell)

Indicators Substances used to test the presence of a specific substance Many times an indicator will change color when it combines with its specific molecule Benedict’s Solution – turns from blue to yellow in the presence of glucose Iodine – changes from amber to dark blue in the presence of starch Paper Towel – turns shiny when a lipid is placed on its surface To find DNA we use many different indicators, such as luminol

Carbohydrates or Sugars These molecules are composed of a carbon, two hydrogen molecules, and an oxygen or any multiples of this. CH2O Monosaccharide – a simple sugar that cannot be broken down into any smaller units (taste really sweet) Examples: glucose, and fructose Glucose – C6H12O6 Polysaccharide – a complex sugar composed of two or more monosaccharides (not sweet) Examples: starch, and cellulose C O H

Carbohydrates Living things use carbohydrates as their main source of energy (plants store this energy in the form of starch, when we eat plants we break this starch down and harness the energy that plants were storing) Carbohydrates contain energy in their bonds, so during digestion when these bonds are broken energy is released. Carbohydrates are macromolecules (large molecules synthesized by combining smaller subunits) The subunits of carbohydrates are simple sugars (monosaccharide)

Lipids A large molecule composed of a glycerol and fatty acids These molecules are hydrophobic (afraid of water); they will not mix with water Example: oil in water They can be used to store energy as well They make up the membranes and steroids found in living things

Nucleic Acids These are the subunits that make up DNA and RNA Nucleic Acids contain nitrogen, so they are sometimes referred to as the nitrogen base of DNA or RNA They combine with a sugar and a phosphate molecule to create a nucleotide Nucleotides combine to make a strand of DNA DNA is how we pass hereditary information on from one generation to the next

Proteins Proteins can also be called polypeptides Proteins are made by sticking many different amino acids together Amino Acids are compounds that contain an amino group (-NH2) and a carboxyl group (-COOH), so they contain nitrogen Enzymes are one category of protein, but they are special because they help catalyze reactions Catalyze – speed up a reaction

Enzymes Enzymes make reactions possible because they act as a catalyst. Most reactions do not occur spontaneously, they need an input of energy to occur. This energy is called ACTIVATION ENERGY. Catalysts (enzymes) speed up the rate of a chemical reaction by reducing the amount of activation energy needed for a reaction to occur. Without a catalyst most reactions in our body would not be possible Enzymes are shape specific with their substrate Activation energy without Catalyst Activation energy with Catalyst