ORGANIC CHEMISTRY

Organic compounds always contain carbon and hydrogen.

Inorganic compounds typically lack carbon.

• 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.

Organic Compounds

Table 2.3.1

• 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

Organic Compounds

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

• Are important for structure and as energy sources.

• Consist of C, H, and O with the formula (CH2O)n

Carbohydrates

Figure 2.8

• 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.

Carbohydrates

MONOSACCHARIDES

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

• Monosaccharides are simple sugars with 3 to 7 carbon atoms.

Carbohydrates

Figure 2.8

STRUCTURAL ISOMERS

• IDENTICAL MOLECULAR FORMULAS• DIFFERENT STRUCTURES

• 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.

Carbohydrates

Figure 2.8

DISACCHARIDES

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

POLYSACCHARIDES

• STARCH• GLYCOGEN• CELLULOSE• CHITIN

STARCH GLYCOGEN

• STORAGE MOLECULE IN PLANTS

• 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

• ARE THE PRIMARY COMPONENTS OF CELL MEMBRANES.

• CONSIST OF C, H, AND O.• ARE NONPOLAR AND INSOLUBLE IN

WATER.

Lipids

• Called fats or triglycerides contain glycerol and fatty acids; formed by dehydration synthesis.

NEUTRAL FATS

Figure 2.9c

SATURATED VS UNSATURATED FATS

TYPES OF NEUTRAL FATS

• MONOGLYCERIDE• DIGLYCERIDE• TRIGLYCERIDE

– COMMON STORAGE MOLECULE

• Contain C, H, and O + P, N, or S.

• Membranes are made of phospholipids

PHOSPHOLIPIDS

Figure 2.10a

• Consist of four carbon rings, with an –OH group attached to one ring.

• Are part of membranes.

Steroids

Figure 2.11

• 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.Proteins

Table 2.4.1

Proteins

Table 2.4.2

AMINO ACID STRUCTURE

• AMINE GROUP• CARBOXYL• REMAINDER OF THE MOLECULE

• Exist in either of two stereoisomers, D or L.

• L-forms are most often found in nature.

Amino Acids

Figure 2.13

PEPTIDE BONDING

• COVALENT• DIPEPTIDES• POLYPEPTIDES

• Peptide bonds between amino acids are formed by dehydration synthesis.

Peptide Bonds

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.

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

MODIFICATIONS OF PROTEINS

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

• Consist of nucleotides.• Nucleotides consist of a:

• Pentose• Phosphate group• Nitrogen-containing (purine or pyrimidine) base

Nucleic Acids

Figure 2.16

• Has deoxyribose

• Exists as a double helix

• A hydrogen bonds with T

• C hydrogen bonds with G

DNA

Figure 2.16

THE NUCLEOTIDES

• PURINES• DOUBLE RING

– ADENINE– GUANINE

• PYRIMIDINE• SINGLE RING

– GUANINE– THYMINE

DNA STRUCTURE

• LINEAR STRANDS• BONDS BETWEEN

SUGARS AND PHOSPHATES

• DOUBLE HELIX

• Has ribose• Is single-stranded• A hydrogen bonds

with U• C hydrogen bonds

with G

RNA

Figure 2.17

TYPES OF RNA

• mRNA –CODES FOR PROTEINS• tRNA---CARRIES AMINO ACIDS• Rrna---STRUCTURAL COMPONENT OF

RIBOSOMES

• Has ribose, adenine, and 3 phosphate groupsATP

Figure 2.18

CYCLIC NUCLEOTIDES

• NUCLEOTIDE CONVERTED TO CYCLIC FORM– CYCLASES

• IMPORTANT IN SECOND MESSENGER SYSTEMS

• REGULATING CELL FUNCTION• cAMP & cGMP

DINUCLEOTIDES

• IMPORTANT FOR METABOLIC PROCESS

• NICOTINAMIDE ADENINE DINUCLEOTIDE –NAD+– ELECTRON AND HYDROGEN DONOR

AND ACCEPTOR– OXIDATION AND REDUCTIONS

• Is made by dehydration synthesis.• Is broken by hydrolysis to liberate useful energy

for the cell.

ATP