Organic Chemistry

Molecules of Life Put C, H, O, N together in different ways to build living organisms What are bodies made of? carbohydrates sugars & starches proteins fats (lipids) nucleic acids DNA, RNA

Don’t forget water organic molecules Water 65% of your body is H2O water is inorganic doesn’t contain carbon Rest of you is made of carbon molecules organic molecules carbohydrates proteins fats nucleic acids 5

Carbon atoms have unique bonding properties. Carbon-based molecules have three general types of structures. straight chain branched chain ring

The molecules of life Organic molecules contain carbon Carbohydrates, lipids, proteins, and nucleic acids are 4 types. Inorganic molecules constitute nonliving matter, but they are still important to us. Salts, water, acids, bases, and carbon dioxide are examples.

Building Organic Molecules Carbon can bond to as many as 4 different atoms AND it can bond to itself. Long chains of carbon atoms as well as rings of carbon atoms form. Small molecules (monomers) join to form large macromolecules (polymers).

Building Organic Molecules Hydrocarbon Chain

Building Organic Molecules Monomer Polymer Functional Groups

Types of Organic Molecules - Carbohydrates Supply our body with energy Made up of sugars Glucose and fructose combine to form sucrose Glucose combines with other glucose molecules to form starch, glycogen, and cellulose

The “skinny” on carbohydrates Starch is formed by plants when they store sugar. Glycogen is formed by animals when they store sugar. Cellulose is found in the cell walls of plants and since we cannot digest it, it passes through our intestines as fiber.

Linear and ring forms of glucose H H C OH HO C H H C O C 1 2 3 4 5 6 OH 4 C 6 CH2OH 5 C H OH 2 C 1C 3 C 2C 1 C CH2OH HO 3 2 (a) Linear and ring forms. Chemical equilibrium between the linear and ring structures greatly favors the formation of rings. To form the glucose ring, carbon 1 bonds to the oxygen attached to carbon 5. (b) Abbreviated ring structure. Each corner represents a carbon. The ring’s thicker edge indicates that you are looking at the ring edge-on; the components attached to the ring lie above or below the plane of the ring.

Starch and cellulose structures (c) Cellulose: 1– 4 linkage of  glucose monomers H O CH2OH OH HO 4 C 1 (a)  and  glucose ring structures (b) Starch: 1– 4 linkage of  glucose monomers  glucose  glucose

Carbohydrates Monomers are monosaccharides Include simple sugars and complex carbohydrates called starches Molecules contain carbon, hydrogen, and oxygen Function as main source of energy; also structural purposes such as cell walls of plants, fungi, and bacteria.

Lipids Supply our body with energy Also insulate us against heat loss and cushion major organs Made up of glycerol and 3 fatty acids (a.k.a. triglyceride)

Lipids Saturated fatty acids make the lipid solid at room temperature Every carbon has a H at every place possible Liquid fats contain unsaturated fatty acids Some carbons do not have H where one could be bonded

The synthesis and structure of a fat, or triglycerol (b) Fat molecule (trilglycerol) H O H C OH Glycerol Fatty acid (palmitic acid) HO O (a) Dehydration reaction in the synthesis of a fat Ester linkage

Saturated vs. Unsaturated Fatty Acids

Lipids are not just for chewing Fats and oils are present in the foods we eat. Phospholipids have a phosphate head and only 2 fatty acid chains; they form our cells’ membranes. Steroids are made up of 4 carbon rings Cholesterol, estrogen, and testosterone are examples.

Phospholipid Structure and Shape Phospholipids in the Cell Membrane

Lipids Monomers: a glycerol group and up to three fatty acids Examples are fats, oils Molecules contain mostly carbon and hydrogen (long hydrocarbon chains or tails) Functions include long term stored energy, insulation, some hormones and steroids

The emulsification of fats Because fats do not disperse in liquids easily, diets high in saturated fats and cholesterol can lead to hardening of the arteries. Bile is secreted during digestion to help fats disperse in the liquid contents of our stomach and intestine.

Proteins Proteins have many functions Provide structure Act as hormones Contract our muscles Transport molecules in the blood Act as antibodies and enzymes In our cell membranes, form channels and transport molecules

Proteins (con’t) Are made up of amino acids 20 amino acids exist 12 of these 20 amino acids are made by the body; 8 must be ingested! Amino acid chains fold upon themselves to form 3-D shapes which determine the function of the protein Denaturation is caused by heat and changes in pH.

The 20 amino acids of proteins H3N+ C CH3 CH CH2 NH H2C H2N Nonpolar Glycine (Gly) Alanine (Ala) Valine (Val) Leucine (Leu) Isoleucine (Ile) Methionine (Met) Phenylalanine (Phe) Tryptophan (Trp) Proline (Pro) H3C O O–

Polar Electrically charged OH CH2 C H H3N+ O CH3 CH SH NH2 Polar Electrically charged –O NH3+ NH2+ NH+ NH Serine (Ser) Threonine (Thr) Cysteine (Cys) Tyrosine (Tyr) Asparagine (Asn) Glutamine (Gln) Acidic Basic Aspartic acid (Asp) Glutamic acid (Glu) Lysine (Lys) Arginine (Arg) Histidine (His)

Proteins Monomers are amino acids Examples include meats. Milk and eggs contain protein. Molecules contain hydrogen, oxygen, carbon, nitrogen, and sometimes sulfer (S) Functions include fighting disease, transports substances into or out of cells, control the rate of chemical reactions.

Nucleic Acids Monomers are nucleotides. Nucleotides have three subunits: a phosphate group, a pentose sugar, and a nitrogenous base. Examples are DNA and RNA Molecules contain hydrogen, oxygen, nitrogen, carbon, and phosphorous Functions include storing and tranferring genetic information

The components of nucleic acids CH Uracil (in RNA) U 5’ end 5’C O 3’ end OH Nitrogenous base Nucleoside O O P CH2 Phosphate group Pentose sugar (b) Nucleotide C N H NH2 HN CH3 Cytosine Thymine (in DNA) T HC NH Adenine A Guanine G Purines HOCH2 5’ 4 3’ 2’ 1’ 3’ 2’ Pentose sugars Deoxyribose (in DNA) Ribose (in RNA) Nitrogenous bases Pyrimidines (c) Nucleoside components (a) Polynucleotide, or nucleic acid

Nucleic acids Contain the genetic information needed to sustain life and are used in protein synthesis Are made up of nucleotides DNA – phosphate, sugar, and the bases A, T, G, C RNA – phosphate, sugar, and the bases A, U, G, C ATP – 3 phosphates, sugar, and the base A

The DNA double helix and its replication 3¢ end Sugar-phosphate backbone Base pair (joined by hydrogen bonding) Old strands Nucleotide about to be added to a new strand A 5¢ end New strands C G T

ATP = cellular energy When we digest food, sugars enter the mitochondria of our cells where cellular respiration occurs. We store the energy released as sugar is broken down in ATP molecules (ADP + P  ATP) When our cells need energy, ATP is broken down into ADP.

Review To reinforce the concept of polymers(many) made from repeating monomers(one). Complete the following chart: Monomer Polymer

Check your answers To reinforce the concept of polymers(many) made from repeating monomers(one). Complete the following chart: Monomer- (subunits) Polymer (macro molecules) Monosaccharide (simple sugars) polysaccharides starches- cellulose Amino acids proteins Nucleotides nucleic acids Fatty acids lipids(triglycerides) Lipids are smaller than true polymers and are not made of repeating units. Monosaccharides (simple sugars) -- polysaccharides starches-cellulose Amino acids proteins Nucleotides nucleic acids Fatty acids lipids(triglycerides) 24

Draw a mark at the midpoint of a sheet of paper along the side edge. Then fold the top and bottom edges in to touch the midpoint.

Fold in half from side to side.

Open and cut along the inside fold lines to form four tabs.

Label each tab.

As you read in the text, draw the structure and list the characteristics of carbohydrates, lipids, proteins, and nucleic acids under the appropriate tabs. Include structure, what each is made of (subunits), uses, and examples

Dehydration synthesis and Hydrolysis Dehydration synthesis (AKA condensation) is the process in living things that builds molecules. Monomers are bonded together to form polymers. Hydrolysis is the process in living things that break down molecules. This is what happens during digestion.

Making a polypeptide chain DESMOSOMES OH CH2 C N H O Peptide bond SH Side chains H2O Amino end (N-terminus) Backbone (a) Carboxyl end (C-terminus) (b)

Examples of disaccharide synthesis Dehydration reaction in the synthesis of maltose. The bonding of two glucose units forms maltose. The glycosidic link joins the number 1 carbon of one glucose to the number 4 carbon of the second glucose. Joining the glucose monomers in a different way would result in a different disaccharide. Dehydration reaction in the synthesis of sucrose. Sucrose is a disaccharide formed from glucose and fructose. Notice that fructose, though a hexose like glucose, forms a five-sided ring. (a) (b) H HO H OH OH O CH2OH H2O 1 2 4 1– 4 glycosidic linkage 1–2 glycosidic linkage Glucose Fructose Maltose Sucrose

1. Each table will get two different colored glucose molecules 2 1. Each table will get two different colored glucose molecules 2. Join (bond) the two glucoses together by cutting off an –H from one molecule and an –OH from another. Tape the 2 together 3. Take the trimmed H-OH, attach it to the water drop, and tap that onto the bottom of the bond 4. Name your molecule! Remember – it needs to end in -ose