ORGANIC CHEMISTRY Organic compounds always contain carbon and

ORGANIC CHEMISTRY Organic compounds always contain carbon and hydrogen. Inorganic compounds typically lack carbon.

Organic Compounds • The chain of carbon atoms in an organic molecule is the carbon skeleton. • Functional groups are responsible for most of the chemical properties of a particular organic compound.

Table 2. 3. 1

Organic Compounds • Small organic molecules can combine into large macromolecules. • Macromolecules are polymers consisting of many small repeating molecules. • The smaller molecules are called monomers.

Organic Compounds • Monomers join by dehydration synthesis or condensation reactions. • Polymers are broken apart by hydrolysis or phosphorlysis Figure 2. 8

CARBOHYDRATES, LIPIDS, PROTEINS, AND NUCLEIC ACIDS • BIOLOGICAL MOLECULES ARE ORGANIC COMPOUNDS • CARBOHYDRATES • FATS AND LIPIDS • PROTEINS • NUCLEIC ACIDS

CARBOHYDRATES • MONOSACCHARIDES = SUGARS • DISACCHARIDES = SUGARS • POLYSACCHARIDES = STARCHES & CELLULOSE

Carbohydrates • Are important for structure and as energy sources. • Consist of C, H, and O with the formula (CH 2 O)n Figure 2. 8

Carbohydrates • Oligosaccharides consist of 2 to 20 monosaccharides. • Polysaccharides consist of tens or hundreds of monosaccharides joined through dehydration synthesis. • Starch, glycogen, dextran, and cellulose are polymers of glucose that are covalently bonded differently. • Chitin is a polymer of two sugars repeating many times.

MONOSACCHARIDES • • • GLYCERALDHYDE 3 PHOSPHATE ERYTHROSE 4 PHOSPHATE RIBOSE 5 PHOSPHATE GLUCOSE FRUCTOSE GALACTOSE

Carbohydrates • Monosaccharides are simple sugars with 3 to 7 carbon atoms. Figure 2. 8

STRUCTURAL ISOMERS • IDENTICAL MOLECULAR FORMULAS • DIFFERENT STRUCTURES

Carbohydrates • Disaccharides are formed when two monosaccharides are joined in a dehydration synthesis. • The bond is a glycosidic bond • Disaccharides can be broken down by hydrolysis. Figure 2. 8

DISACCHARIDES • MALTOSE—GLUCOSE + GLUCOSE • SUCROSE—GLUCOSE + FRUCTOSE • LACTOSE---GLUCOSE + GALACTOSE

POLYSACCHARIDES • • STARCH GLYCOGEN CELLULOSE CHITIN

STARCH • STORAGE MOLECULE IN PLANTS GLYCOGEN • STORAGE MOLECULE IN ANIMALS

CELLULOSE • MOST ABUNDANT CARBOHYDRATE • PLANT • ALGAE

CHITIN • FUNGI CELL WALLS • EXOSKELETON OF INSECTS

GLUCOSAMINE & GALACTOSAMINE • MODIFIED CARBOHYDRATES • HYDROXIDE GROUP REPLACED BY AMINE GROUP

LIPIDS • • • NEUTRAL FATS PHOSPHOLIPIDS STEROIDS WAXES TWICE AS MUCH ENERGY PER GRAM THAN CARBOHYDRATES

Lipids • ARE THE PRIMARY COMPONENTS OF CELL MEMBRANES. • CONSIST OF C, H, AND O. • ARE NONPOLAR AND INSOLUBLE IN WATER.

NEUTRAL FATS • Called fats or triglycerides contain glycerol and fatty acids; formed by dehydration synthesis. Figure 2. 9 c

SATURATED VS UNSATURATED FATS

TYPES OF NEUTRAL FATS • MONOGLYCERIDE • DIGLYCERIDE • TRIGLYCERIDE – COMMON STORAGE MOLECULE

PHOSPHOLIPIDS • Contain C, H, and O + P, N, or S. • Membranes are made of phospholipids Figure 2. 10 a

Steroids • Consist of four carbon rings, with an –OH group attached to one ring. • Are part of membranes. Figure 2. 11

PROTEINS • ARE ESSENTIAL IN CELL STRUCTURE AND FUNCTION. • ENZYMES ARE PROTEINS THAT SPEED CHEMICAL REACTIONS. • TRANSPORTER PROTEINS MOVE CHEMICALS ACROSS MEMBRANES. • FLAGELLA ARE MADE OF PROTEINS. • SOME BACTERIAL TOXINS ARE PROTEINS.

Proteins • Consist of subunits called amino acids. Table 2. 4. 1

Proteins Table 2. 4. 2

AMINO ACID STRUCTURE • AMINE GROUP • CARBOXYL • REMAINDER OF THE MOLECULE

Amino Acids • Exist in either of two stereoisomers, D or L. • L-forms are most often found in nature. Figure 2. 13

PEPTIDE BONDING • COVALENT • DIPEPTIDES • POLYPEPTIDES

Peptide Bonds • Peptide bonds between amino acids are formed by dehydration synthesis. Figure 2. 14

PEPTIDE BONDS • Peptide bonds between amino acids are broken by hydrolysis.

PROTEIN STRUCTURE • • PRIMARY SECONDARY TERTIARY QUATRENARY

PRIMARY STRUCTURE • SEQUENCE OF AMINO ACIDS

SECONDARY STRUCTURE • ALPHA HELIX • BETA SHEET

TERTIARY STRUCTURE • DETERMINES THE BIOLOGICAL FUNCTION OF THE MOLECULE

QUATERNARY STRUCTURE • COMBINES PROTEINS WITH TWO OR MORE SUBUNITS • The tertiary structure occurs when the helix folds irregularly, forming disulfide bonds, hydrogen bonds, and ionic bonds between amino acids in the chain.

MODIFICATIONS OF PROTEINS • Conjugated proteins consist of amino acids and other organic molecules: • Glycoproteins • Nucleoproteins • Lipoproteins

CLASSIFICATION OF PROTEINS BY FUNCTION • • • ENZYMES STRUCTURAL PROTEINS CONTRACTILE PROTEINS HORMONES TRANSPORT PROTEINS DEFENSE PROTEINS

ENZMES • MOST ENZYMES ARE PROTEINS • CATALYSTS FOR CHEMICAL REACTIONS

STRUCTURAL PROTEINS • • PARTS OF CELLS AND TISSUES COLLAGEN ELASTIN KERATIN

CONTRACTILE PROTEINS • ACTIN • MYOSIN

HORMONE • INTERCELLULAR MESSENGERS • INSULIN • GROWTH HORMONE

TRANSPORT PROTEINS • HEMOGLOBIN& MYOGLOBIN • ALBUMIN

DEFENSE PROTEINS • IMMNOGLOBULIN • FIBRINOGEN

CLASSIFICATION OF PROTEINS BY SOLUBILITY • • GLOBULAR PROTEINS FIBROUS PROTEINS LIPOPROTEINS GLYCOPROTEINS NUCLEOPROTEINS CHROMOPROTEINS METALLOPROTEINS

GLOBULAR PROTEINS • POLAR NATURE • MOST NUMEROUS OF PROTEINS – ENZYMES – PLASMA PROTEINS – CELL MEMBRANE PROTEINS

FIBROUS PROTEINS • INSOLUBLE • ELONGATE TO FORM STRONG FIBERS • STRUCTURAL AND SUPPORTING FIBERS – ELASTIN, KERATIN, MYOSIN AND FIBRIN

CLASSIFICATION BY COMPOSITION • • • LIPOPROTEINS GLYCOPROTEINS NUCLEOPROTEINS CHROMOPROTEINS METALLOPROTEINS

LIPOPROTEINS • CONTAIN FAT AND OTHER LIPIDS

GLYCOPROTEINS • CONTAIN SUGARS

NUCLEOPROTEINS • BOUND TO NUCLEIC ACIDS

CHROMOPROTEINS • CONTAINS HEME GROUP

METALLOPROTEINS • CONTAIN METAL IONS

NUCLEIC ACIDS • • RNA = RIBONUCLEIC ACID DNA = DEOXIRIBONUCLEIC ACID DOUBLE HELIX RESPONSIBLE FOR PROTEIN SYNTHESIS

Nucleic Acids • Consist of nucleotides. • Nucleotides consist of a: • Pentose • Phosphate group • Nitrogen-containing (purine or pyrimidine) base Figure 2. 16

DNA • Has deoxyribose • Exists as a double helix • A hydrogen bonds with T • C hydrogen bonds with G Figure 2. 16

THE NUCLEOTIDES • PURINES • DOUBLE RING • PYRIMIDINE • SINGLE RING – ADENINE – GUANINE – THYMINE

DNA STRUCTURE • LINEAR STRANDS • BONDS BETWEEN SUGARS AND PHOSPHATES • DOUBLE HELIX

RNA • Has ribose • Is single-stranded • A hydrogen bonds with U • C hydrogen bonds with G Figure 2. 17

TYPES OF RNA • m. RNA –CODES FOR PROTEINS • t. RNA---CARRIES AMINO ACIDS • Rrna---STRUCTURAL COMPONENT OF RIBOSOMES

ATP • Has ribose, adenine, and 3 phosphate groups Figure 2. 18

CYCLIC NUCLEOTIDES • NUCLEOTIDE CONVERTED TO CYCLIC FORM – CYCLASES • IMPORTANT IN SECOND MESSENGER SYSTEMS • REGULATING CELL FUNCTION • c. AMP & c. GMP

DINUCLEOTIDES • IMPORTANT FOR METABOLIC PROCESS • NICOTINAMIDE ADENINE DINUCLEOTIDE –NAD+ – ELECTRON AND HYDROGEN DONOR AND ACCEPTOR – OXIDATION AND REDUCTIONS

ATP • Is made by dehydration synthesis. • Is broken by hydrolysis to liberate useful energy for the cell.