2 Polymers Are Built of Monomers Organic molecules are formed by living organisms.Carbon-based coreThe core has attached groups of atoms called functional groups.The functional groups confer specific chemical properties on the organic molecules.
3 Five principal functional groups Found InGroupStructuralFormulaBall-and-Stick ModelO–POOHCHNLipidsProteinsDNA,ATPCarbohydratesCarboxylCarbonylHydroxylAminoPhosphate3
4 MacromoleculesThe building materials of the body are known as macromolecules because they can be very large.There are four types of macromolecules:ProteinsNucleic acidsCarbohydratesLipids
5 MacromoleculesLarge macromolecules are actually assembled from many similar small components, called monomers.The assembled chain of monomers is known as a polymer.
6 Dehydration Synthesis All polymers are assembled the same way.A covalent bond is formed by removing a hydroxyl group (OH) from one subunit and a hydrogen (H) from another subunit.
7 Dehydration Synthesis Because this amounts to the removal of a molecule of water (H2O), this process of linking together two subunits to form a polymer is called dehydration synthesis.HEnergyHOH2O
8 Hydrolysis H2O H Energy HO The process of disassembling polymers into component monomers is essentially the reverse of dehydration synthesis.A molecule of water is added to break the covalent bond between the monomers.This process is known as hydrolysis.HHOEnergyH2O
9 ProteinsProteins are complex macromolecules that are polymers of many subunits called amino acids.
10 ProteinsThe covalent bond linking two amino acids together is called a peptide bond.The assembled polymer is called a polypeptide.OCNHH2ORAmino acidOHPolypeptide chain
11 ProteinsAmino acids are small molecules with a simple basic structure, a carbon atom to which three groups are added:an amino group (—NH2)a carboxyl group (—COOH)a functional group (R)The functional group gives amino acids their chemical identity.There are 20 different types of amino acids.
12 Proteins Protein structure is complex. The order of the amino acids that form the polypeptide is important.The sequence of the amino acids affects how the protein folds together.
13 ProteinsThe way that a polypeptide folds to form the protein determines the protein’s function.Some proteins are comprised of more than one polypeptide.
14 Proteins There are four general levels of protein structure: Primary Secondarystructureβ-pleated sheetα-helixTertiaryQuaternaryAmino acidsPrimaryThere are four general levels of protein structure:PrimarySecondaryTertiaryQuaternary
15 ProteinsPrimary structure—the sequence of amino acids in the polypeptide chain.Determines all other levels of protein structure.Amino acidsPrimarystructure
16 ProteinsSecondary structure forms because regions of the polypeptide that are nonpolar are forced together; hydrogen bonds can form between different parts of the chain.The folded structure may resemble coils, helices, or sheets.NHCOSecondarystructureβ-pleated sheetα-helix
17 Proteins Tertiary structure—the final 3-D shape of the protein. The final twists and folds that lead to this shape are the result of polarity differences in regions of the polypeptide.Tertiarystructure
18 ProteinsQuaternary structure—the spatial arrangement of proteins comprised of more than one polypeptide chain.Quaternarystructure
19 Proteins The shape of a protein affects its function. DenaturationFoldedproteinDenatured proteinThe shape of a protein affects its function.Changes to the environment of the protein may cause it to unfold or denature.Increased temperature or lower pH affects hydrogen bonding, which is involved in the folding process.A denatured protein is inactive.
20 ProteinsActive-sitecleftEnzymes are globular proteins that have a special 3-D shape that fits precisely with another chemical.They cause the chemical that they fit with to undergo a reaction.This process of enhancing a chemical reaction is called catalysis.
21 Nucleic AcidsNucleic acids are very long polymers that store information.Comprised of monomers called nucleotides.Each nucleotide has 3 parts:a five-carbon sugara phosphate groupan organic nitrogen-containing base
22 Nucleic Acids There are five different types of nucleotides. Information is encoded in the nucleic acid by different sequences of these nucleotides.NOP–OO–RCHH3C45132287639451Structure of nucleotideNitrogenous baseNitrogenous basesGuanineUracil (RNA only)SugarThymine (DNA only)CytosinePhosphate groupH in DNAOH in RNAAdenineOHCH2NH2(a)(b)
23 Nucleic Acids There are two types of nucleic acids: GCATPhosphodiester bondHydrogen bondsbetween nitrogenousbasesSugar-phosphate“backbone”OHThere are two types of nucleic acids:Deoxyribonucleic acid (DNA)Ribonucleic acid (RNA)RNA is similar to DNA except thatit uses uracil instead of thymineit is comprised of just one strandit has a ribose sugar
24 Nucleic Acids The structure of DNA is a double helix because: There are only two base pairs possibleAdenine (A) pairs with thymine (T)Cytosine (C) pairs with Guanine (G)Properly aligned hydrogen bonds hold each base pair together.A sugar-phosphate backbone comprised of phosphodiester bonds gives support.
25 AGCTG and C can align to formthree hydrogen bonds.A and T can align to formtwo hydrogen bonds.G and T cannot properlyalign to form hydrogenbonds.A and C cannot properly
26 Nucleic Acids The structure of DNA helps it to function. The hydrogen bonds of the base pairs can be broken to unzip the DNA so that information can be copied.Each strand of DNA is a mirror image so that the DNA contains two copies of the information.Having two copies means that the information can be accurately copied and passed to the next generation.
27 CarbohydratesCarbohydrates are monomers that make up the structural framework of cells and play a critical role in energy storage.A carbohydrate is any molecule that contains the elements C, H, and O in a 1:2:1 ratio.
28 Carbohydrates The sizes of carbohydrates varies: Simple carbohydrates—consist of one or two monomers.Complex carbohydrates—are long polymers.
29 Carbohydrates Simple carbohydrates are small. Monosaccharides consist of only one monomer subunit.An example is the sugar glucose (C6H12O6).Disaccharides consist of two monosaccharides.An example is the sugar sucrose, which is formed by joining together glucose and fructose.
30 Carbohydrates Complex carbohydrates are long polymer chains. Because they contain many C-H bonds, these carbohydrates are good for storing energy.These bond types are the ones most often broken by organisms to obtain energy.The long chains are called polysaccharides.
31 CarbohydratesPlants and animals store energy in polysaccharide chains formed from glucose.Plants form starch.Animals form glycogen.Some polysaccharides are structural and resistant to digestion by enzymes.Plants form cellulose cell walls.Some animals form chitin for exoskeletons.
32 Lipids Lipids—fats and other molecules that are not soluble in water. Lipids are nonpolar molecules.There are many different types of lipids.fatsoilssteroidsrubberwaxespigments
33 Lipids Fats are converted from glucose for long-term energy storage. Fats have two subunits1. fatty acids2. glycerolFatty acids are chains of C and H atoms, known as hydrocarbons.The chain ends in a carboxyl (—COOH) group.
34 Saturated and unsaturated fats Because there are 3 fatty acids attached to a glycerol, another name for a fat is triglycerideHCO(a) Fat molecule (triacylglycerol)GlycerolbackboneFatty acids
35 LipidsFatty acids have different chemical properties due to the number of hydrogens that are attached to the non-carboxyl carbonsIf the maximum number of hydrogens are attached, then the fat is said to be saturated.If there are fewer than the maximum attached, then the fat is said to be unsaturated.
36 Saturated and unsaturated fats HHHHCCCCHH(b) Hard fat (saturated): Fattyacids with single bondsbetween all carbon pairs(c) Oil (unsaturated): Fatty acidsthat contain double bondsbetween one or more pairsof carbon atoms
37 Phospholipids Biological membranes involve lipids. Phospholipids make up the two layers of the membrane.Cholesterol is embedded within the membrane.Outside of cellCarbohydrate chainsCellmembraneMembrane proteinsPhospholipidCholesterolInside of cell