Chapter 2 The Chemistry of Life Section 3 Carbon Compounds

Organic Chemistry The study of all compounds that contains bonds between carbon atoms

The Chemistry of Carbon Each electron can form with an electron from another atom to form strong covalent bonds. Carbon atoms have 4 valence electrons. Carbon can bond with almost any other element. Carbon atoms can also bond with other carbon atoms.

Carbon chains Because carbon can bond with other carbon atoms, it can form chains. Chains can be any length. Carbon – carbon bonds can be single, double or triple covalent bonds. Chains can form into rings

Figure 2-11 Carbon Compounds Section 2-3 Methane Acetylene Butadiene Benzene Isooctane Go to Section:

Macromolecules Giant molecules are Formed by polymerization – large compounds are built by joining smaller ones together. Monomers are smaller units that join together to form polymers

Four groups of organic compounds (macromolecules) Carbohydrates Lipids Nucleic acids Proteins

Carbohydrates Compounds made up of carbon, hydrogen and oxygen atoms. Are the main source of energy for living things. Provides quick energy – easily and quickly enter the bloodstream

Energy source Simple carbohydrates – sugars such as glucose, fructose and galactose. Breakdown and give immediate energy for cell activities. Complex carbohydrates – starches. Living things store extra sugar as starch

Figure 2-13 A Starch Section 2-3 Starch Glucose Go to Section:

Sugars Monosaccharides – single sugar molecules. Examples: galactose, fructose Polysaccharides – large macromolecules formed from monosaccharides Examples: glycogen (animal starch). Use: When glucose runs low, glycogen is released from the liver and provides energy

Sugars, continued Example: Plant starch – stores excess sugar Example: Cellulose – structural polysacchride; gives plants strength and rigidity

Lipids Fats, oils, waxes, steroids Not water soluble Made mostly from carbon and hydrogen atoms Contains some oxygen atoms Steroids – cholesterol, bile, cortisone, sex hormones (testosterone, progesterone)

Lipids Saturated fats – contain the maximum amount of H atoms; Ex. Meat and dairy products Unsaturated fats – contains one carbon-carbon double bond Ex. Nuts, vegetable oil, fish Polyunsaturated – contains more than one carbon-carbon double bond. Ex. Cooking oils

Lipids Functions in living organisms include: Energy source (slow breakdown) Insulation Cushion and protect organs Component of membranes (phospholipids) Chemical messengers – send information between cell organelles and other cells

Nucleic Acids Macromolecules containing hydrogen, oxygen, nitrogen, carbon and phosphorous. Composed of nucleotides Nucleotides – consist of a 5-carbon sugar, a phosphate group, and a nitrogenous base.

Nucleic acids Store and transmit genetic information Two kinds: RNA – ribonucleic acid DNA – deoxyribonucleic acid

Proteins Macromolecules that contain nitrogen as well as carbon, hydrogen and oxygen. Are polymers of molecules called amino acids (20 different amino acids) (Translation – proteins are chains of amino acids linked together by peptide bonds)

Figure 2-16 Amino Acids General structure Alanine Serine Section 2-3 Amino group Carboxyl group General structure Alanine Serine Go to Section:

Amino Acids DNA contains the instructions for arranging amino acids into proteins. Each protein has a different role: Control rate of reactions within a cell Regulate cell processes Form bones and muscles Transport substances into or out of cells to help fight disease

Section 2-3 Figure 2-17 A Protein Amino acids Go to Section:

Assignment Make a compare/contrast table entitled: Four Groups of Organic Compounds Column Titles are: Group Name Chemical Composition Examples Functions in Living Things