3. Click on a lesson name to select. Chapter 6 Chemistry in Biology Section 1: Atoms, Elements, and Compounds Section 2: Chemical Reactions Section 3: Water and Solutions Section 4: The Building Blocks of Life

4. Click on a lesson name to select. Objective: Identify the particles that makeup atoms. Diagram the particles that make up an atom.

5. Atoms  Chemistry is the study of matter.  Matter is anything that has mass and occupies space. 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 center of the atom in the nucleus.  Protons are positively charged particles.  Neutrons are particles that have no charge.

6. NameLocationCharge ProtonNucleusPositive NeutronNucleusNeutral ElectronEnergy levelsnegative

7. The first energy level holds 2 electrons. 2 nd energy level holds 8 electrons

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

9. The number of neutrons is calculated by subtracting the atomic number from the atomic mass of the element. Ex. Carbon has the atomic number of 6 and an atomic mass of 12. Therefore, it has 6 neutrons (12-6=6).

10. Elements Chemistry in Biology  An element is a pure substance that cannot be broken down into other substances by physical or chemical means.  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

11. The elements are arranged on the periodic table by their atomic number which is the number of protons for that element.

12. The Periodic Table of Elements Chemistry in Biology  Horizontal rows are called periods.  Vertical columns are called groups.  Elements in a group have similar properties. 6.1 Atoms, Elements, and Compounds Chapter 6

14. Hydrogen 1 H 1.008 Element Atomic number Symbol Atomic mass

15. Isotopes Chemistry in Biology  Isotopes are 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

16. Radioactive Isotopes Chemistry in Biology  Radioisotopes give off radiation when the nucleus splits. This radiation can be detected and used for many applications. 6.1 Atoms, Elements, and Compounds Chapter 6

17. “SPONCH” – common elements of human body - www.chem.ufl.edu

18. Compounds Chemistry in Biology  A compound is formed when two or more different elements combine.  The combination of elements will be in a fixed ratio. Ex. water – H 2 O  Compounds cannot be broken down into simpler compounds or elements by physical means. 6.1 Atoms, Elements, and Compounds Chapter 6

19. Objective Compare and contrast covalent bonds and ionic bonds.

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

21. Ionic Bonds Chemistry in Biology  Ionic bonds form when two oppositely charged atoms are attracted to each other. Electrons are transferred. 6.1 Atoms, Elements, and Compounds Chapter 6

22. Metals donate electrons. Nonmetals accept electrons. An ion is an atom that has lost or gained one or more electrons.

23. Chemistry in Biology Chapter 6

24.  Most ionic compounds are crystalline at room temperature and have higher melting points than molecular compounds formed by covalent bonds.  Ionic liquids are more environmentally friendly. Chemistry in Biology 6.1 Atoms, Elements, and Compounds Chapter 6

25. Chemistry in Biology van der Waals Forces  van der Waals forces are attractive forces between molecules. 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

26. Reactants and Products  A chemical reaction is the process by which atoms or groups of atoms in substances are reorganized into different substances by breaking or forming chemical bonds. Ex. rust 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

27. A physical change alters the substance’s appearance not composition. A chemical change involves a change in composition of a substance.

28. 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.  The arrow means yields. 6.2 Chemical Reactions Chapter 6

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

30. Chemistry in Biology Balanced Equations  The law of conservation of mass states matter cannot be created or destroyed.  All chemical reactions must balance. 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

31. The coefficient is the number in front of the reactant or product. The subscript is the number of atoms. The coefficient times the subscript equals the total number of atoms.

32. 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

33. Chemistry in Biology  An exothermic reaction releases energy in the form of heat.  The energy of the product is lower than the energy of the reactants. 6.2 Chemical Reactions Chapter 6

34. Chemistry in Biology  An endothermic absorbs heat energy.  The energy of the products is higher than the energy of the reactants. 6.2 Chemical Reactions Chapter 6

35. Endothermic or Exothermic?

36. Chemistry in Biology  A catalyst is a substance that lowers the activation energy needed to start a chemical reaction.  Catalysts are not used up in a 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

37. 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

38. Chemistry in Biology  Factors such as pH, temperature, and other substances 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.

39. Chemistry in Biology Chapter 6

40. 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. Water is a polar compound.  A hydrogen bond is a weak interaction involving a hydrogen atom and a fluorine, oxygen, or nitrogen atom. (#3) Chapter 6

41. Chemistry in Biology 6.3 Water and Solutions Chapter 6 Visualizing Properties of Water Enzyme- Controlled Reactions

42. Mixtures A mixture is a combination of two or more substances in which each substance retains its individual characteristics. There are two types: –Heterogeneous mixtures –Homogeneous mixtures

43. Chemistry in Biology Homogenous Mixtures  A homogenous mixture has a uniform composition throughout the mixture. Ex. food coloring in water  Solvent + solute = solution  A solvent is a substance in which another substance is dissolved.  A solute is the substance that is dissolved in the solvent. #10 Food coloring dissolved in water forms a homogenous mixture. 6.3 Water and Solutions Chapter 6

44. Water is the universal solvent because many substances dissolve in it. (#7) Water is adhesive (sticks to surfaces) which allows it to travel up the stem of a plant. (#8) Water is cohesive (molecules stick together) which causes water to form droplets. (#9)  A solute is the substance that is dissolved in the solvent. (#10)

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

46. A suspension is a heterogeneous mixture in which the particles settle out over time. Ex. sand and water

47. A colloid is a heterogeneous mixture in which the particles do not settle out over time. Ex. milk, mayonnaise, paint, blood.

48. 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

49. 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

50. 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

51. Organic Chemistry  The element carbon is a component of almost all biological molecules. 6.4 The Building Blocks of Life Chemistry in Biology Chapter 6

52.  Carbon has four electrons in its outermost energy level.  One carbon atom can form four covalent bonds with other atoms. This enables carbon atoms to bond to each other which results in a variety of important organic compounds. (#2) 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

53. Macromolecules, also called polymers 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 monomers (repeating units of identical or nearly identical compounds linked together by a series of covalent bonds).(#4) 6.4 The Building Blocks of Life Chapter 6

54. The four major categories of macromolecules are carbohydrates, lipids, proteins, and nucleic acids.

57. Chemistry in Biology Chapter 6

58. GroupExampleFunctionMonomerComponents __________Bread  Stores energy  Structural support monosaccharide_________ Lipids___________  Store energy  steroids  waterproofs coatings Fatty acid and ___________ C, H ___________Hemoglobin  transports substances  speeds reaction structural support  hormones ___________ C,N, O,H, S Nucleic acids___________  Stores and communicates genetic information __________Phosphate N-base Ribose sugar

59. Chemistry in Biology Carbohydrates  Compounds composed of carbon, hydrogen, and oxygen in a ratio of one oxygen and two hydrogen atoms for each carbon atom—(CH 2 O) n 6.4 The Building Blocks of Life Chapter 6

60. 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.

61. Chemistry in Biology Lipids  Molecules 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

62. Saturated and Unsaturated Fats

63. Chemistry in Biology  Saturated fats (lipids) have tail chains made up of only single bonds between the carbon atoms.  Unsaturated fats have tail chains with at least one double bond between the carbon atoms.  Fats with more than one double bond in the tail are called polyunsaturated fats. 6.4 The Building Blocks of Life Chapter 6

64. Chemistry in Biology Proteins  Proteins are made of 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

65. Chemistry in Biology  Amino acids have a central carbon atom.  One of the four carbon bonds is with hydrogen.  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

66. Chemistry in Biology Chapter 6

67. 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

68. Chemistry in Biology  Nucleic acids are complex macromolecules that store and transmit genetic information.  The two nucleic acids are DNA and RNA.  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

69. Chemistry in Biology Chapter Resource Menu Chapter Diagnostic Questions Formative Test Questions Chapter Assessment Questions Standardized Test Practice biologygmh.com Glencoe Biology Transparencies Image Bank Vocabulary Animation Chapter 6 Click on a hyperlink to view the corresponding lesson.

70. A. electron B. isotope C. neutron D. proton 1.Which of the following particles is negatively charged? Chemistry in Biology Chapter 6 Diagnostic Questions (1-31) Chapter 6

71. A. electrons B. neutrons C. protons D. ions 2. Isotopes are created by a change in the number of what particle of an atom? Chemistry in Biology Chapter 6 Diagnostic Questions Chapter 6

72. A. substrates B. enzymes C. ions D. reactants 3. Identify the proteins that speed up the rate of chemical reactions. Chemistry in Biology Chapter 6 Diagnostic Questions Chapter 6

73. A. neutrons and electrons B. protons and electrons C. protons and neutrons D. protons, neutrons and electrons 4. What particles are in an atom’s nucleus? Chemistry in Biology 6.1 Formative Questions Chapter 6

74. A. an equal number of protons and neutrons B. an equal number of protons and electrons C. an equal number of neutrons and electrons D. an unequal number of protons and electrons 5. What causes the overall charge of an atom to be zero? Chemistry in Biology 6.1 Formative Questions Chapter 6

75. A. a compound B. an element C. an isotope D. a mixture 6. What type of substance is water? Chemistry in Biology 6.1 Formative Questions Chapter 6

76. A. chemical bonds B. ionic compounds C. radioactive isotopes D. van der Waals forces 7. What provides the energy for all living processes? Chemistry in Biology 6.1 Formative Questions Chapter 6

77. A. a match burning B. salt dissolving C. water boiling D. gasoline evaporating 8. Which is a chemical reaction? Chemistry in Biology 6.2 Formative Questions Chapter 6

78. 9. Which chemical reaction is endothermic? Chemistry in Biology A. B. 6.2 Formative Questions Chapter 6

79. A. It acts as a reactant. B. It reduces the amount of heat produced. C. It increases the amount of product. D. It lowers the activation energy. 10. How does an enzyme increase the rate of a chemical reaction? Chemistry in Biology 6.2 Formative Questions Chapter 6

80. 11. What occurs at the active site in the enzyme substrate complex? Chemistry in Biology 6.2 Formative Questions Chapter 6

81. Chemistry in Biology 6.2 Formative Questions Chapter 6 A. An exothermic chemical reaction takes place. B. Chemical bonds are broken and new bonds are formed. C. The enzyme gets used up in the reaction. D. The substrates provide energy for the enzyme.

82. A. It acts as a catalyst. B. Its pH is neutral. C. It is a polar molecule. D. It is an ionic compound. 12. Why is water able to dissolve a wide variety of solutes? Chemistry in Biology 6.3 Formative Questions Chapter 6

83. A. covalent bonds B. double bonds C. hydrogen bonds D. ionic bonds 13. What type of bonds attracts water molecules to each other and to other substances? Chemistry in Biology 6.3 Formative Questions Chapter 6

84. A. Cl – B. OH – C. H + D. Na + 14. Which ion, when released in water, causes a solution to be basic? Chemistry in Biology 6.3 Formative Questions Chapter 6

85. A. alkali B. antacid C. buffer D. neutralizer 15. What is the name for a substance that keeps the pH in cells within the 6.5 to 7.5 pH range? Chemistry in Biology 6.3 Formative Questions Chapter 6

86. A. carbon B. nitrogen C. phosphorus D. sodium 16. Which element do almost all biological molecules contain? Chemistry in Biology 6.4 Formative Questions Chapter 6

87. A. 1 B. 2 C. 4 D. 8 17. How many covalent bonds can carbon form with other atoms? Chemistry in Biology 6.4 Formative Questions Chapter 6

88. A. hormone B. nucleic acid C. protein D. steroid 18. What type of biological molecule is an enzyme? Chemistry in Biology 6.4 Formative Questions Chapter 6

89. A. lipids B. nucleotides C. polypeptides D. sugars 19. What are fats, oils, and waxes composed of? Chemistry in Biology 6.4 Formative Questions Chapter 6

90. A. carbohydrate B. lipid C. nucleic acid D. protein 20. Which biological molecule transports substances between cells? Chemistry in Biology 6.4 Formative Questions Chapter 6

91. A. amino acids B. fatty acids C. glycerols D. nucleotides 21. What are the monomers that make up proteins? Chemistry in Biology 6.4 Formative Questions Chapter 6

92. A. activation energy B. reactants C. products D. enzymes 22. Look at the following figure. Determine what the upward curve represents. Chemistry in Biology Chapter Assessment Questions Chapter 6 ?

93. A. 2 B. 4 C. 6 D. 8 23. Look at the energy levels in the atom. What is the maximum number of electrons energy level two can hold? Chemistry in Biology Chapter Assessment Questions Chapter 6

94. 24. Explain why chemical equations must be balanced. Short answer. Chemistry in Biology Answer: Chemical reactions require balance of mass. Therefore, 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. Chapter Assessment Questions Chapter 6

95. A. atoms sharing electrons B. table salt dissolving in water C. ionic compounds forming crystals D. water molecules forming droplets 25. Which is a result of van der Waals forces? Chemistry in Biology Standardized Test Practice Chapter 6

96. 26. What is true of this chemical reaction? Chemistry in Biology Standardized Test Practice Chapter 6

97. A. Energy is not needed to start the chemical reaction. Chemistry in Biology Standardized Test Practice Chapter 6 B. Heat and/or light energy are released in this reaction. C. The activation energy is greater than the energy released. D. The energy of the products and the reactants is the same.

98. A. tomatoes B. bananas 27. Which fruit contains a higher concentration of hydrogen ions? Chemistry in Biology Standardized Test Practice Chapter 6

99. A. They are energy-storing polymers. B. They are found in the cells of animals. C. They are structural polysaccharides. 28. What do cellulose and chitin have in common? Chemistry in Biology Standardized Test Practice Chapter 6 D. They are composed of repeating sucrose units.

100. A. gluten B. glycogen C. starch D. sucrolose 29. Which polysaccharide stores energy in muscle and liver tissue? Chemistry in Biology Standardized Test Practice Chapter 6

101. 30. What is the function of this biological macromolecule? Chemistry in Biology Standardized Test Practice Chapter 6 A. communicate signals between cells B. produce vitamins and hormones C. provide support and protection D. store and transmit genetic information

102. 31. Which is a characteristic of all lipids? Chemistry in Biology Standardized Test Practice Chapter 6 A. They are saturated triglycerides. B. They do not dissolve in water. C. They are liquid at room temperature. D. They store less energy than carbohydrates.

103. Chemistry in Biology Glencoe Biology Transparencies Chapter 6

104. Chemistry in Biology Image Bank Chapter 6

105. Chemistry in Biology Image Bank Chapter 6

106. atom nucleus proton neutron electron element isotope compound covalent bond molecule ion ionic bond van der Waals force Chemistry in Biology Vocabulary Section 1 Chapter 6

107. chemical reaction reactant product activation energy catalyst enzyme substrate active site Chemistry in Biology Vocabulary Section 2 Chapter 6

108. polar molecule hydrogen bond mixture solution solvent solute acid base pH buffer Chemistry in Biology Vocabulary Section 3 Chapter 6

109. macromolecule polymer carbohydrate lipid protein amino acid nucleic acid nucleotide Chemistry in Biology Vocabulary Section 4 Chapter 6

110.  Ionic Bonds Ionic Bonds  Enzymes Enzymes  Visualizing Properties of Water Visualizing Properties of Water  Polypeptides Polypeptides Chemistry in Biology Animation Chapter 6