1. Biochemistry Notes Unit 3

2. Elements Chemistry in Biology  An element is a pure substance that cannot be broken down  There are over 100 known elements, 92 of which occur naturally.  Each element has a unique name and symbol. 6.1 Atoms, Elements, and Compounds Chapter 6

3. The Periodic Table of Elements Chemistry in Biology  Horizontal rows are called periods.  Vertical columns are called groups. 6.1 Atoms, Elements, and Compounds Chapter 6

4.  Chemistry = study of matter. 6.1 Atoms, Elements, and Compounds  Atoms are the building blocks of matter. Chapter 6 Chemistry in Biology  Neutrons and protons are located at the nucleus of the atom.  Protons are positively charged particles.  Neutrons are particles that have no charge.

5.  Electrons are negatively charged particles that are located outside the nucleus. Chemistry in Biology 6.1 Atoms, Elements, and Compounds Chapter 6

6. Atomic Number: number of protons in the nucleus of an element (atom). 6.1 Atoms, Elements, and Compounds

7. Atomic Mass: the number of protons & neutrons in the nucleus of an element (atom). Find the neutrons only: Atomic mass-atomic number=neutrons Ex: Carbon Picture 6.1 Atoms, Elements, and Compounds

8. Isotopes Chemistry in Biology  Atoms of the same element that have the same number of protons and electrons but have a different number of neutrons 6.1 Atoms, Elements, and Compounds Chapter 6

9. Isotope Clip http://glencoe.mcgraw- hill.com/sites/dl/free/0078695104/164155/ 00038306.html

10. Radioactive Isotopes Chemistry in Biology  When a nucleus breaks apart, it gives off radiation that can be detected and used for many applications. 6.1 Atoms, Elements, and Compounds Chapter 6

11. Compounds Chemistry in Biology  A pure substance formed when two or more different elements combine  Compounds cannot be broken down into simpler compounds or elements by physical means, must be a chemical reaction 6.1 Atoms, Elements, and Compounds Chapter 6

12. Chemical Bonds Chemistry in Biology  Covalent bonds  Chemical bond that forms when electrons are shared  A molecule is a compound in which the atoms are held together by covalent bonds. 6.1 Atoms, Elements, and Compounds Chapter 6

13. Ionic Bonds Chemistry in Biology  Electrical attraction between two oppositely charged atoms or groups of atoms 6.1 Atoms, Elements, and Compounds Chapter 6

14. Chemistry in Biology Chapter 6

15. Chemistry in Biology  The elements identified as metals tend to donate electrons.  The elements identified as nonmetals tend to accept electrons. 6.1 Atoms, Elements, and Compounds Chapter 6  Some atoms donate or accept electrons easier than other atoms.

16. Chemistry in Biology van der Waals Forces  When molecules come close together, the attractive forces between slightly positive and negative regions pull on the molecules and hold them together.  The strength of the attraction depends on the size of the molecule, its shape, and its ability to attract electrons. 6.1 Atoms, Elements, and Compounds Chapter 6

17. Reactants and Products  A chemical reaction is the process by which atoms or groups of atoms in substances are reorganized into different substances. 6.2 Chemical Reactions  Clues that a chemical reaction has taken place include the production of heat or light, and formation of a gas, liquid, or solid. Chemistry in Biology Chemical reaction Physical reaction Chapter 6

18. Chemical Equations Chemistry in Biology  Chemical formulas describe the substances in the reaction and arrows indicate the process of change.  Reactants are the starting substances, on the left side of the arrow.  Products are the substances formed during the reaction, on the right side of the arrow. 6.2 Chemical Reactions Chapter 6

19.  Glucose and oxygen react to form carbon dioxide and water. Chemistry in Biology 6.2 Chemical Reactions Chapter 6

20. Chemistry in Biology Balanced Equations  The law of conservation of mass states matter cannot be created or destroyed.  The number of atoms of each element on the reactant side must equal the number of atoms of the same element on the product side. 6.2 Chemical Reactions Chapter 6

21. Chemistry in Biology  The activation energy is the minimum amount of energy needed for reactants to form products in a chemical reaction. Energy of Reactions 6.2 Chemical Reactions Chapter 6

22. Chemistry in Biology  This reaction is exothermic and released heat energy.  The energy of the product is lower than the energy of the reactants. 6.2 Chemical Reactions Chapter 6

23. Chemistry in Biology  This reaction is endothermic and absorbed heat energy.  The energy of the products is higher than the energy of the reactants. 6.2 Chemical Reactions Chapter 6

24. Chemistry in Biology  A catalyst is a substance that lowers the activation energy needed to start a chemical reaction.  Enzymes are biological catalysts.  It does not increase how much product is made and it does not get used up in the reaction. Enzymes 6.2 Chemical Reactions Chapter 6

25. Chemistry in Biology  The reactants that bind to the enzyme are called substrates.  The specific location where a substrate binds on an enzyme is called the active site. 6.2 Chemical Reactions Chapter 6 Fits together like a lock and key

26. Chemistry in Biology  Factors such as pH, temperature, and the concentrations of substrate & enzyme affect enzyme activity. 6.2 Chemical Reactions Chapter 6  The active site changes shape and forms the enzyme-substrate complex, which helps chemical bonds in the reactants to be broken and new bonds to form.

27. What role do enzymes play in chemical reactions within living organisms? Chemical reaction – process that changes 1 set of chemicals into another set of different chemicals –Reactants – starting chemicals –Products – ending chemicals –Involves breaking of bonds and forming new ones Energy –Either released or absorbed –Activation energy – energy needed to start a reaction

28. Chemistry in Biology Chapter 6

29. Enzyme Review 1.Enzymes are a form of ___. a. carbohydrate b. lipid c. protein 2.Enzymes can speed up a reaction, so they are called ___. a. catalysts b. reactants c. inhibitors 3.The area where the enzyme attaches to the substrate is called the ___. a. active site b. cohesion area c. vectors 4. If the enzyme is heated, it will change shape. This ______ affect the ability of the enzyme to work. a. will b. will not 5.Enzymes work because they lower the ___. a. chemical reactant rate b. active site location c. activation energy

30. Water’s Polarity 6.3 Water and Solutions Chemistry in Biology  Molecules that have an unequal distribution of charges are called polar molecules.  Polarity is the property of having two opposite poles. (Think of North & South Pole)  A hydrogen bond is a weak interaction involving a hydrogen atom and a fluorine, oxygen, or nitrogen atom. Chapter 6

31. Chemistry in Biology 6.3 Water and Solutions Chapter 6

32. Water Polarity & Hydrogen Bond VideoClip http://glencoe.mcgraw- hill.com/olcweb/cgi/pluginpop.cgi?it=swf::5 50::400::/sites/dl/free/0078695104/383915 /CH06_Properties_of_Water_103006.swf:: Visualizing Properties of Water

33. Water properties:  Water is cohesive  Cohesion: attraction between same molecules, causes molecules to draw inward at surface  Ex: allows some insects & spiders can “walk” on the surface  Water is adhesive  Adhesion: attraction between different molecules, causes water to bend at the surface  Ex: capillary action-pulls column of water up to the top of a plant

34. Water properties:  Water is called “Universal solvent”: dissolves many other substances due to polarity  Differences in charges pulls/pushes substances apart (Like a magnet attracts or repels other magnets)  Water exhibits evaporative cooling: removes heat when it evaporates from a surface  Ex: sweating cools skin  Water expands during freezing: expands into crystal formation releasing heat  Ex: rocks broken up by ice creating soil; ice layer protects fruit from freezing

35. Chemistry in Biology Homogenous Mixtures  A mixture that has a uniform composition throughout  A solvent is a substance in which another substance is dissolved.  A solute is the substance that is dissolved in the solvent. Food coloring dissolved in water forms a homogenous mixture. 6.3 Water and Solutions Chapter 6

36. Chemistry in Biology Heterogeneous Mixtures  In a heterogeneous mixture, the components remain distinct. A salad is a heterogeneous mixture. 6.3 Water and Solutions Chapter 6

37. Chemistry in Biology  Substances that release hydrogen ions (H + ) when dissolved in water are called acids.  Substances that release hydroxide ions (OH – ) when dissolved in water are called bases. Acids and Bases 6.3 Water and Solutions Chapter 6

38. Chemistry in Biology  The measure of concentration of H + in a solution is called pH.  Acidic solutions have pH values lower than 7.  Basic solutions have pH values higher than 7. pH and Buffers 6.3 Water and Solutions Chapter 6

39. Chemistry in Biology  Buffers are mixtures that can react with acids or bases to keep the pH within a particular range. 6.3 Water and Solutions Chapter 6

40. Organic Chemistry  The study of all compounds containing the element CARBON 6.4 The Building Blocks of Life Chemistry in Biology Chapter 6

41. Chemistry in Biology  Carbon compounds can be in the shape of straight chains, branched chains, and rings. 6.4 The Building Blocks of Life Chapter 6

42. What is a macromolecule?  A giant molecule made up of 100’s or 1000’s or smaller units called MONOMERS  Monomers link together to form large POLYMERS  formed by polymerization

43. Macromolecules Chemistry in Biology  Carbon atoms can be joined to form carbon molecules.  Macromolecules are large molecules formed by joining smaller organic molecules together.  Polymers are molecules made from repeating units of identical or nearly identical compounds linked together by a series of covalent bonds. 6.4 The Building Blocks of Life Chapter 6

44. The 4 types of macromolecules: CARBOHYDRATES LIPIDS NUCLEIC ACIDS PROTEINS

45. Chemistry in Biology Carbohydrates  Made up of carbon, hydrogen, and oxygen 6.4 The Building Blocks of Life Chapter 6

46. Chemistry in Biology  Two monosaccharides joined together form a disaccharide.  Longer carbohydrate molecules are called polysaccharides. 6.4 The Building Blocks of Life Chapter 6  Values of n ranging from three to seven are called simple sugars, or monosaccharides.

47. CARBOHYDRATES  Made up of C,H,O  Used as main source of energy Two types:  Sugars: quick source of energy  Monosaccharide-simple sugar, disaccharide-2, polysaccharide-many  Ex: glucose, lactose, fructose, sucrose  Starches: many sugars linked together, source of energy breaking down slower  Used by plants for energy storage  Ex: potatoes, pasta, bread, grains

48. Starch Glucose Section 2-3 Figure 2-13 A Starch Go to Section:

49. Chemistry in Biology Lipids  Made mostly of carbon and hydrogen  A triglyceride is a fat if it is solid at room temperature and an oil if it is liquid at room temperature. 6.4 The Building Blocks of Life Chapter 6

50. Chemistry in Biology  Lipids that have tail chains with only single bonds are called saturated fats.  Lipids that have at least one double bond in the tail chain are called unsaturated fats.  Fats with more than one double bond in the tail are called polyunsaturated fats. 6.4 The Building Blocks of Life Chapter 6

51. LIPIDS  Made up mainly of C & H  Used to store energy, insulation & protection  Usually not soluble in water  Saturated: has maximum number of H bonds, usually solid at room temperature  Unsaturated: at least one double bond, usually liquid

52. Chemistry in Biology Proteins  A compound made of small carbon compounds called amino acids  Amino acids are small compounds that are made of carbon, nitrogen, oxygen, hydrogen, and sometimes sulfur. 6.4 The Building Blocks of Life Chapter 6

53. Chemistry in Biology  The other three bonds are with an amino group (–NH 2 ), a carboxyl group (–COOH), and a variable group (–R). 6.4 The Building Blocks of Life Chapter 6

54. PROTEINS  Made up of C,H,O,N  Made up of groups called amino acids (20 in nature)  proteins have a large variety of sizes & shapes  If the shape changes, it becomes a new protein  Ex: when you boil an egg, the protein changes color, shape  Found in muscles, cell membrane

55. Chemistry in Biology  The number and the order in which the amino acids are joined define the protein’s primary structure.  After an amino acid chain is formed, it folds into a unique three-dimensional shape, which is the protein’s secondary structure, such as a helix or a pleat. 6.4 The Building Blocks of Life Chapter 6

56. Chemistry in Biology  Nucleic acids are complex macromolecules that store and transmit genetic information.  Nucleic acids are made of smaller repeating subunits called nucleotides, composed of carbon, nitrogen, oxygen, phosphorus, and hydrogen atoms. 6.4 The Building Blocks of Life Chapter 6

57. Nucleic Acids  Made up of H,O,N,C & P  Store and transmit genetic information  Made up of nucleotides  Two types: DNA & RNA

58. QUESTIONS?