ORGANIC COMPOUNDS Chapter 2 Section 3

Organic Compounds are made mostly of carbon atoms most molecules with carbon are organic exception: carbon dioxide, carbon monoxide Carbon has 4 valence electrons so readily forms 4 covalent bonds

Organic Compounds

CARBOHYDRATES COMPOSED OF : Functions: C, H, O in ratio of: 1:2:1 *Energy Source Simple carbohydrates Energy storage Complex carbohydrates Structural materials Cell surface markers

Carbohydrates exist as: SIMPLE MONOSACCHARIDES GLUCOSE FRUCTOSE GALACTOSE DISACCHARIDES SUCROSE glucose & fructose MALTOSE glucose &glucose LACTOSE glucose & galactose COMPLEX POLYSACCHARIDES Made of 3 or more monosaccharides ANIMALS: GLYCOGEN LIVER PLANTS: STARCH CELLULOSE (wood)

GLUCOSE

GLYCOGEN

CELLULOSE

PROTEINS are large organic molecules composed mainly of : C, H, O, N (a little S) Building blocks are AMINO ACIDS ALL SHARE SAME BASIC STRUCTURE

Amino Acids Side Groups: Provide different shape Polar or Nonpolar

Functions of Proteins Structural Proteins Transport Proteins Enzymes Hair, nails, hooves Transport Proteins Carry molecules through blood that otherwise would not be soluble in blood Carry ions or molecules across membranes Enzymes Catalyze all chemical reactions in body Specific to a single chemical reaction Muscles Actin, myosin in all 3 muscle types

Peptide Bonds Form when 2 amino acids join in a synthesis reaction (condensation)

Types of Proteins Dipeptides Polypeptides A + B  AB Long chains of amino acids In large proteins 2 to 4 polypeptide chains fold together Interact through hydrogen bonds or disulfide bridges

Protein Shape Determines function Influenced by: Temperature pH Solvent

Lipids C H O NOT a polymer long chains of carbon – carbon bonds with hydrogen; oxygen at end of molecule called fatty acids

LIPIDS are large, nonpolar organic molecules include: Triglycerides Cholesterol Phospholipids Steroids Waxes Pigments

Fatty Acids Unbranched carbon chains that make up most lipids one end has a carboxyl group so is hydrophilic other end is hydrocarbon so is hydrophobic Saturated Fatty Acids each C has only single covalent bonds Unsaturated Fatty Acids some C atoms have double covalent bonds which put kinks in the chain

Fatty Acids

Triglycerides composed of 3 molecules of fatty acid joined to 1 molecule of glycerol high melting points (solids at room temperature) butter, fat in red meat

Phospholipids have 2 fatty acid chains attached to a molecule of glycerol plus a phosphate group attached to the 3rd carbon in glycerol makes up most of cell membrane in a lipid bilayer are nonpolar so keeps most polar substances from crossing membrane

Waxes are a structural lipid made of long fatty acid chain with a long alcohol chain are waterproof so act as protective layer in plants & animals

Steroids composed of 4 fused carbon rings with various functional groups attached includes many hormones Testosterone Estrogen Progesterone Adrenal hormones

NUCLEIC ACIDS very large, complex organic molecules function: subunit: nucleotides C H O N P function: Store & transfer genetic information examples: DNA: deoxyribonucleic acid Genetic code Essential for making proteins RNA: ribonucleic acid Produce proteins Few act like enzymes

Nucleotides 3 parts: 5 carbon sugar Phosphate group (- charge) RNA: ribose DNA: deoxyribose Phosphate group (- charge) Nitrogenous base

NUCLEIC ACIDS DNA RNA