Section 2.3 Carbon Compounds

Organic Chemistry

• Organic Chemistry- Study of all compounds that contain bonds between carbon atoms

I. Chemistry of Carbon

• Characteristics of Carbon:1. Carbon atoms have 4 valence electrons2. Each electron can join with an electron from

another atom to form a strong covalent bond3. Carbon can bond with many elements such as

• Hydrogen• Oxygen• Phosphorus• Sulfur• NitrogenSPONCH

Characteristics of Carbon

4. Carbon atoms can bond to other carbon atoms forming chains that are almost unlimited in length (macromolecules)

5. Carbon-carbon bonds can be• Single (C-C)• Double (C=C)• Triple (C C)

Characteristics of Carbon

Chains of carbon can even form ringsNo other element has the versatility as

carbon!

MacromoleculesMacromolecules- large molecules made from

1000s or 100s of 1000s smaller molecules • Made by a process of polymerization• Made of smaller units called monomers joined

together to form polymers (the monomers can be identical or different!)

Organic compounds or biomolecules are classified into 4 groups:

1. Carbohydrates2. Lipids3. Nucleic Acids 4. Proteins

1. Carbohydrates

Living things use carbohydrates as their main source of energy and structural purposes

The breakdown of sugars, such as glucose (C6H12O6) supplies immediate energy for all cell activity

1. Carbohydrates

Extra sugar is stored as complex carbohydrates known as starchesa) Monosaccharide- single sugar molecules such as

glucose, galactose (milk), and fructose (fruits)

b) Disaccharide- two monosaccharides linked together

a) Polysaccharide- many monosaccharides joined together

Ex. Glycogen- animal starch released from your liver when glucose in blood runs lowCellulose- plant starch which is tough and flexible. Major component of wood and paper

2. Lipids

Lipids- fats, oils, and waxesCompounds made mostly from carbon and

hydrogenNOT soluble in water!Used to store energy

2. LipidsServes an important role in biological

membranes and waterproof coveringsMany lipids are formed when a glycerol

molecule combines with compounds called fatty acids

2. Lipidsa) Saturated- carbon atom in a lipids fatty acid chain is

joined to another carbon atom by a single bond (maximum number of hydrogens!)

b) Unsaturated- at least one carbon-carbon double bond in a fatty acid (ex. Olive oil)

c) Polyunsaturated- fatty acids contain more than one double bond (ex. Cookingoils such as corn, sesame, canola and peanut oils)

3. Nucleic Acids

Nucleic Acids- Macromolecules that contain hydrogen, oxygen, nitrogen, carbon and phosphorusa) Nucleotide- individual monomer consisting of a

5-carbon sugar, a phosphate group, and a nitrogenous base (A, T, C, or G)

3. Nucleic Acids

– Individual nucleotides can be joined by covalent bonds to form a nucleic acid

– Nucleic acids store and transmit heredity or genetic information1. DNA- deoxyribonucleic acid (sugar=deoxyribose)2. RNA- ribonucleic acid (sugar = ribose)

4. ProteinsMacromolecules that contain nitrogen,

carbon, hydrogen, and oxygenMonomers are called amino acidsAmino acids are compounds with an amino

group (-NH2) on one end and a carboxyl group (-COOH) on the other end

4. ProteinsThere are more than 20

different amino acids found in nature

Amino acids are joined by covalent bonds

The instructions for arranging amino acids into many different proteins are stored in DNA

4. Proteins

1. Proteins have a specific role– Control rate of reactions (enzymes)– Regulate cell processes (hormones)– Transport substances into or out of cells– Help fight disease (antibodies)– Form bones and muscles

4. Proteins2. Proteins may have up

to 4 levels of organization1st- sequence of amino acids in a protein chain2nd- amino acids can be twisted or folded3rd- chain is folded

* Van der Waal’s forces and hydrogen bonds help maintain the shape of the protein

III. Enzymes

Enzymes- biological catalysts that cells use to speed up chemical reactions within a cell

Enzymes speed up reactions by lowering the activation energy

Activation Energy- the amount of energy needed to initiate a chemical reaction

Most enzymes work best at a certain pH and certain temperatures

Enzymes

Enzymes play essential roles ini. Regulating chemical pathwaysii. Making materials that cells need iii. Releasing energyiv. Transferring information

Red = without enzymeGreen = with enzyme