The Building Blocks of Life

1. The Building Blocks of Life

2. Organic Compounds • Are carbon containing compounds • Carbon has the ability to form covalent bonds that are strong and stable

3. Carbohydrates • Commonly known as sugars and starches • CHO-means that the compound contains carbon, hydrogen, and oxygen in a ratio of 1:2:1; is also the abbreviation for carbohydrates • The primary function of carbohydrates is to store and release energy • There are three categories of CHO, mono, di, and polysaccharides

4. Monosaccharides *are the simplest carbohydrates; contain one sugar Ex. Glucose-sugar green plants produce and most living organisms use as their energy source • Ex. Galactose; found in milk • Ex. Fructose; found in fruits • Chemical formula for each monosaccharide is C6H12O6 The arrangement of the atoms makes each compound different. Therefore, they are isomers of each other.

5. Structural Formulas of Simple Sugars

6. Disaccharides *Composed of two simple sugars or monosaccharides • Ex. Sucrose (glucose + fructose); table sugar • Ex. Maltose (glucose + glucose); malt sugar • Ex. Lactose (glucose + galactose); milk sugar • Molecular formula C12H22O11 • can derive the formula by dehydration synthesis

7. Polysaccharides • Are the largest carbohydrate molecule • Composed of at least three monosaccharides • Is the form in which living things store excess sugar • Ex. Starch, cellulose, and glycogen • Molecular formula is (C6H10O5)n • n=the # of repeating units

8. Starch consists of highly branched chains of glucose units and is used as food storage by plants; potatoes and grains • Cellulose another glucose polymer that forms the cell walls of plants and gives structural support (strength and rigidity); made of glucose units hooked together like a chain-link fence; found in plants and is a major component of wood

9. Glycogen-animals store food in this form; is another polymer, but is more highly branched than starch; found in the liver and muscles of animals

10. The Structure of Lipids • Are organic compounds with a large proportion of C-H bonds and less O2 than CHO • Commonly called fats, oils, and waxes; fats and waxes are usually solids at room temp., oils are liquids; waxes consist of one fatty acid linked to an alcohol • Are insoluble in water because their molecules are non-polar (not attracted by H2O)

11. Most common type consists of 3 fatty acids bonded to a molecule of glycerol; triglyceride • Lipids have various functions • Can be used to store energy • Used to form biological membranes • Act as chemical messengers (use it as a starting material for making other steroids, including male and female sex hormones) • Steroids are lipids; cholesterol is an example • Too much cholesterol may lead to artherosclerosis

12. Types of Lipids or Fats • Saturated fats occur when every carbon (C) atom in a fatty acid chain is joined to another C by a single bond; found in meats, most dairy products • Unsaturated fats occur when a pair of C atoms is joined by one double bond • Polyunsaturated fats occur when a fatty acid contains at least two double bonds; tend to be liquids at room temp; Ex. Cooking oils such as olive, corn, canola, and peanut oils

13. Sterols (Steroids) play a number of important roles in building cells and carrying messages from one part of the body to another: Ex. Cholesterol • used for vitamin D synthesis • Used for bile salts • Membrane structure • Steroid hormone synthesis • Phospholipids are molecules that consist of parts that dissolve well in water and parts that do not; play key roles in forming cell membranes from their ability to form bilayers

14. Proteins • Are essential to all life • Are composed of nitrogen in addition to CHO • Are polymers of amino acids (aa) (building blocks of proteins); long chains of aa produces a protein • Has an amino group on one end and a carboxyl group on the other end

15. Protein Structure

16. Four Levels of Protein Structure

17. Descriptions of 4 Protein Levels • Primary (1st)-linear sequence of amino acids • Secondary (2nd)-part of the polypeptide coils or folds into alpha helices and pleated sheets; twisted or folded • Tertiary (3rd)-overall 3D shape of the polypeptide; fibrous or globular • Quaternary (4th)-consists of 2 or more polypeptide chains or subunits • Van der Waals forces and hydrogen bonds help maintain a protein’s shape

18. Seven Classes of Proteins • Structural-silk of spiders and hair fibers • Contractile-muscle movement • Storage-ovalbumin (egg white); source of amino acids for developing embryos • Defensive-antibodies fight infection • Transport-hemoglobin transports oxygen in the bloodstream • Signal-hormones help coordinate body activities (sending messages) • Enzymes-serve as chemical catalysts to speed up reactions

19. Nucleic Acids • Large, organic molecules (macromolecules) composed of CHONP atoms • Stores information in cells in the form of a code • Are polymers of individual monomers known as nucleotides • Nucleotides are composed of a 5C sugar, a nitrogenous base, and a phosphate (PO4 group) • Are two types; DNA and RNA • DNA is the master copy of an organism’s information code; it forms the genetic code • RNA forms a copy of DNA for use in protein synthesis

20. DNA vs RNA • DNA consists of a double helical structure; it contains the sugar deoxyribose, and the bases adenine, thymine, cytosine, guanine • RNA consists of a single strand; it contains the sugar ribose, and the bases adenine, uracil, cytosine, and guanine

21. Enzymes

22. Enzymes • Are proteins • Speed up a reaction by binding to the reactants (substrates). • Substrates bind to enzymes at a region known as the active site. • Are very specific; a particular enzyme can catalyze only one particular chemical reaction involving specific substrates.

23. Enzymes • Are important in regulating chemical pathways, synthesizing materials, needed by cells, releasing energy and transferring information. • Are involved in digestion, respiration, reproduction, vision, movement, thought, and in the making of other enzymes.

24. Enzymes • Are catalysts that work by lowering the ”start-up” energy of a reaction. • Every enzyme has conditions for which it is most effective. • Temperature affects molecular motion. • Optimal temperature produces the highest rate of contact between reactant molecules and the enzyme's active site.

25. Enzymes • Higher temperature denatures the enzymes, altering it’s specific 3-D shape and destroying it’s function. • Salt concentration and pH also influence enzyme activity. • Optimal pH is between 6-8. • Outside this range, enzyme action and normal chemical functioning of cells maybe impaired.

26. The Effect of an Enzyme on EA

27. Enzyme Substrate Complex

28. Competitive Inhibition

29. Noncompetitive Inhibitors

30. Properties of WATER

31. Properties of Water • Serves as a means of transport of materials in organisms; ex. Plant sap and blood are mostly water • Is a polar molecule (a molecule that has an unequal distribution of charges); it also easily attracts other H2O molecules • Makes up about 70-95% of most organisms • Composed of 2 atoms of H+ linked by covalent bonds to 1 atom of O2

32. Structural Formulas of Water

33. Water is the most abundant compound in nearly all living organisms • Water is slightly charged on each end; makes it good at forming mixtures (solutions and suspensions) Solutions-the molecules are uniformly spread throughout the water • Solvent does the dissolving; solute is the substance that is dissolved • Water is the universal solvent Suspensions are mixtures of water and non dissolved materials

34. The Uniqueness of Water • Has a high surface tension; ex. H2O skier, water strider • Cohesion-attraction between molecules of the same substance • Adhesion-attraction between molecules of different substances • Water creeps up in thin tubes; capillary action Ex. Plants get H2O from the ground • Has a high heat of vaporization; Ex. Helps cool the body when sweating • Resists temperature change; water must lose a lot of heat when it cools; requires more heat to increase the temperature than do most other common substances

35. Water expands when it freezes; Ex. If H2O freezes inside the cracks of rocks, it often breaks apart the rocks forming soil over a long period of time.

36. Acids, Bases, and pH • pH scale-indicates the concentration of H+ ions in solutions • Acids-any compound that forms H+ ions in solution; acidic solutions contain a higher concentration of these ions than pure water and have pH values below 7 • Bases-a compound that produces OH- ions in solution; basic or alkaline solutions contain lower concentrations of H+ ions that pure water and has pH values above 7 • Buffers-dissolved compounds; weak acids or bases that can react with strong acids or bases to prevent sharp, sudden change in pH