Chapter 2The Chemistry of Life
Section 1: The Nature of         Matter
Objectives• What three subatomic particles make up  atoms?• How are all the isotopes of an element  similar?• What are the...
The Big Idea• Life Depends on chemistry• Chemical reactions keep you  alive
Atom• Basic unit of matter
Democrites
Subatomic particles• Protons - Positively charged (+)        Bind together                                          to for...
Element• A pure substance that consists  of just one type of atom
An elements atomic number = number ofprotons                            Atomic number                  6                C ...
Isotope• Atoms of the same element  that differ in the number of  neutrons they contain
Nonradioactive carbon-12   Nonradioactive carbon-13   Radioactive carbon-14        6 electrons               6 electrons  ...
The Sum of protons and neutrons in the nucleus of anatom is its mass number                         6                     ...
• The weighted average of the  masses of an elements isotope is  called its atomic mass
Radioactive isotopes• Can be dangerous• Can be used  practically – Radioactive dating – Treat cancer – Kill bacteria
Compounds• A substance formed by the  chemical combination of two or  more elements in definite  proportions• Ex) H2O, NaCl
Table Salt
Ionic Bonds• Formed when one or more  electrons are transferred from  one atom to another
Sodium atom (Na)          Chlorine atom (Cl)   Sodium ion (Na+)   Chloride ion (Cl-)                  Transfer            ...
• If an atom loses an electron it  becomes positive• If an atom gains an electron it  becomes negative
Ions• Positively and negatively  charged atoms
Covalent Bonds• Forms when electrons are  shared between atoms
Molecule• The structure that results when  atoms are joined together by a  covalent bond• Smallest unit of most compounds
Van der Waals Forces• A slight attraction that  develops between the  oppositely charged regions of  nearby molecules due ...
Homework
1. Describe the structure of an atom.   Atoms are made up of protons and   neutrons in a nucleus. Electrons are   in const...
3. What is a covalent bond?   A bond formed when electrons are  shared between atoms4. What is a compound? How are they  r...
5. How do Van der Waals forces hold molecules together? When the sharing of electrons are unequal, a molecule has regions ...
6. How are ionic bonds and Van der Waals forces similar? How are they different? In both cases, particles are held togethe...
Section 2: Properties of        Water
Objectives• Why are water molecules polar?• What are acidic solutions? What  are basic solutions?
The Big Idea• Much of our planet is covered in  water• Water is necessary for life to exist• If life exists on other plane...
Polarity   (-)     The oxygen atom has           a stronger attraction for           electrons   (+)
Hydrogen Bonds• Because of waters partial  charges, they can attract each  other and create hydrogen bonds• Not as strong ...
Cohesion• Attraction between molecules of  the same substance
Adhesion• Attraction molecules of different  substances
Mixture• Material composed of two or more  elements or compounds that are  physically mixed but not  chemically combined• ...
Solutions• Mixture of two or more  substances in which the  molecules are evenly distributed• Ex.) salt water• Settles out...
Solutions             Cl-  Cl-      Na+                    Na+           WaterWater
Solute• Substance that is dissolved• Ex.) salt
Solvent• The substance that does the  dissolving• Ex.) Water
Suspensions• Mixture of water and non-  dissolved materials• Ex.) sugar solution, blood• Separate into pieces so small,  t...
The pH scale• Indicated the concentration of  hydrogen ions in a solution
AcidNeutral  Base
Acids• Any compound that forms H+  (hydrogen) ions in solution
Base• A compound that produces OH-  (hydroxide) ions in solution
Buffers• Weak acids or bases that can  react with strong acids or bases  to prevent sharp, sudden pH  changes
Homework
1. Use the structure of a water   molecule to explain why its polar   Oxygen atom has greater   attraction for electrons, ...
2. Compare acidic and basic solutions in terms of their H+ ion and OH- ion concentrations Acid have more H+ ions than OH- ...
3. What is the difference between a solution and a suspension? In a solution, all components are evenly distributed. In a ...
4. What does pH measure? The concentration of H+ ions in a solution5. The strong acid hydrogen floride (HF) can be dissolv...
Section 3: Carbon Compounds
Objective• What are the functions of each  group of organic compounds?
Interest Grabber Section 2-3   Life’s backbone• Most of the compounds that make up living  things contain carbon. In fact,...
Methane   Acetylene   Butadiene   Benzene   Isooctane
Macromolecules “giant molecules”• Formed by a process called  polymerization
Monomers• Smaller units
Polymers• Linked up monomers
Carbohydrates• Compounds made up of carbon,  hydrogen, and oxygen atoms  usually in a ratio of 1:2:1• Main source of energ...
• Single sugar molecules are called  monosaccharides• The large macromolecules formed  from monosaccharides are known  as ...
Starch         Glucose
Lipids• Made mostly from carbon and  hydrogen atoms• Used to store energy
Lipid   GlycerolFatty Acids
Proteins• Macromolecules that contain  nitrogen as well as carbon,  hydrogen, and oxygen• Proteins are polymers of  molecu...
Amino Acids          Carboxyl groupGeneral structure          Alanine   Serine
• More than 20 different amino  acids, can join to any other amino  acid• The instructions for arranging  amino acids into...
ProteinsAminoAcids
Nucleic Acids• Macromolecules containing hydrogen,  oxygen, nitrogen, carbon, and  phosphorus Double Helix
Nucleotides • Consists of 3 parts: 5-carbon sugar,   phosphate group and nitrogen base                                   N...
2 kinds of nucleic acids• RNA (ribonucleic acids) –  contains sugar ribose• DNA (deoxyribonucleic acid) –  contains sugar ...
Homework
1. Name four groups of organic compounds   found in living things   carbohydrate, lipid, protein, nucleic acids2. Describe...
3. Compare the structures and functions of lipids and starches Lipids are made from carbon and hydrogen. Starches are made...
Section 4: ChemicalReactions and Enzymes
Objectives• What happens to chemical bonds  during chemical reactions?• How do energy changes affect  whether a chemical r...
The Big Idea• Living things are made up of  chemical compounds• Everything that happens to an  organism is based on chemic...
Chemical Reactions• A process that changes or  transforms one set of chemicals  into another
Reactants• Elements or compounds that  enter into a reaction
Products• Elements or compounds  produced by a chemical reaction
Example Reaction: Getting      rid of carbon dioxide • In the bloodCO2 + H20  H2CO3 (carbonic acid) • In the lungsH2CO3 ...
Energy in reactions      Energy-Absorbing Reaction         Energy-Releasing Reaction                       Products       ...
Activation Energy• The energy that is needed to get  a reaction started
Enzymes• Some chemical reactions are too  slow or have activation energies  that are too high to make them  practical for ...
Catalyst• Substance that speeds up the  rate of chemical reactions• Work by lowering a reactions  activation energy
Enzyme•   Biological catalysts•   Speed up reactions in cells•   Very specific•   Named for the reaction is catylzes•   En...
Reaction pathwaywithout enzyme             Activation energy                           without enzymeReactants            ...
Substrates• The reactants of enzyme  catalyzed reactions• The active site of the enzyme and  the substrate have  complemen...
Enzyme Action  Enzyme – substrate complex
Enzyme      ADP      (hexokinase)                      Glucose                                                            ...
Regulation of Enzyme Activity• Enzymes are affected by any  variable that affects chemical  reactions1. pH2. Temperature3....
Homework
1. What happens to chemical bonds   during chemical reactions   Bonds are broken in reactants and   new bonds are formed i...
3. What are enzymes, and how are they important to living things? Enzymes are biological catylasts. Cells use enzymes to s...
4. Describe how enzymes work, including the role of the enzyme substrate complex Substrates, the reactants of an enzyme-ca...
5. A change in pH can change the  protein. How might a change in pH  affect the function of an enzyme such  as hexokinase ...
Biology - Chp 2 - The Chemistry Of Life - PowerPoint
Biology - Chp 2 - The Chemistry Of Life - PowerPoint
Biology - Chp 2 - The Chemistry Of Life - PowerPoint
Biology - Chp 2 - The Chemistry Of Life - PowerPoint
Biology - Chp 2 - The Chemistry Of Life - PowerPoint
Biology - Chp 2 - The Chemistry Of Life - PowerPoint
Biology - Chp 2 - The Chemistry Of Life - PowerPoint
Biology - Chp 2 - The Chemistry Of Life - PowerPoint
Biology - Chp 2 - The Chemistry Of Life - PowerPoint
Biology - Chp 2 - The Chemistry Of Life - PowerPoint
Biology - Chp 2 - The Chemistry Of Life - PowerPoint
Biology - Chp 2 - The Chemistry Of Life - PowerPoint
Biology - Chp 2 - The Chemistry Of Life - PowerPoint
Biology - Chp 2 - The Chemistry Of Life - PowerPoint
Biology - Chp 2 - The Chemistry Of Life - PowerPoint
Upcoming SlideShare
Loading in …5
×

Biology - Chp 2 - The Chemistry Of Life - PowerPoint

3,519 views

Published on

Published in: Education
0 Comments
1 Like
Statistics
Notes
  • Be the first to comment

No Downloads
Views
Total views
3,519
On SlideShare
0
From Embeds
0
Number of Embeds
3
Actions
Shares
0
Downloads
59
Comments
0
Likes
1
Embeds 0
No embeds

No notes for slide
  • Sodium – silver colored metal, soft enough to cut with a knife
  • Sodium reacting explosively in water
  • Chlorine – poisonous green gas used to kill many people in WWII
  • Combination of sodium and chlorine
  • Biology - Chp 2 - The Chemistry Of Life - PowerPoint

    1. 1. Chapter 2The Chemistry of Life
    2. 2. Section 1: The Nature of Matter
    3. 3. Objectives• What three subatomic particles make up atoms?• How are all the isotopes of an element similar?• What are the two types of chemical bonds?
    4. 4. The Big Idea• Life Depends on chemistry• Chemical reactions keep you alive
    5. 5. Atom• Basic unit of matter
    6. 6. Democrites
    7. 7. Subatomic particles• Protons - Positively charged (+) Bind together to form the• Neutrons - Not charged (neutral) nucleus• Electrons - Negatively charged (-) Protons Electrons Nucleus Neutrons
    8. 8. Element• A pure substance that consists of just one type of atom
    9. 9. An elements atomic number = number ofprotons Atomic number 6 C Carbon 12.011
    10. 10. Isotope• Atoms of the same element that differ in the number of neutrons they contain
    11. 11. Nonradioactive carbon-12 Nonradioactive carbon-13 Radioactive carbon-14 6 electrons 6 electrons 6 electrons 6 protons 6 protons 6 protons 6 neutrons 7 neutrons 8 neutrons
    12. 12. The Sum of protons and neutrons in the nucleus of anatom is its mass number 6 C Carbon Mass number 12.011
    13. 13. • The weighted average of the masses of an elements isotope is called its atomic mass
    14. 14. Radioactive isotopes• Can be dangerous• Can be used practically – Radioactive dating – Treat cancer – Kill bacteria
    15. 15. Compounds• A substance formed by the chemical combination of two or more elements in definite proportions• Ex) H2O, NaCl
    16. 16. Table Salt
    17. 17. Ionic Bonds• Formed when one or more electrons are transferred from one atom to another
    18. 18. Sodium atom (Na) Chlorine atom (Cl) Sodium ion (Na+) Chloride ion (Cl-) Transfer of electron Protons +11 Protons +17 Protons +11 Protons +17 Electrons -11 Electrons -17 Electrons -10 Electrons -18 Charge 0 Charge 0 Charge +1 Charge -1
    19. 19. • If an atom loses an electron it becomes positive• If an atom gains an electron it becomes negative
    20. 20. Ions• Positively and negatively charged atoms
    21. 21. Covalent Bonds• Forms when electrons are shared between atoms
    22. 22. Molecule• The structure that results when atoms are joined together by a covalent bond• Smallest unit of most compounds
    23. 23. Van der Waals Forces• A slight attraction that develops between the oppositely charged regions of nearby molecules due to unequal sharing of electrons
    24. 24. Homework
    25. 25. 1. Describe the structure of an atom. Atoms are made up of protons and neutrons in a nucleus. Electrons are in constant motion in the space around the nucleus.2. Why do all isotopes of an element have the same chemical properties They have the same number of electrons
    26. 26. 3. What is a covalent bond? A bond formed when electrons are shared between atoms4. What is a compound? How are they related to molecules A compound is a substance formed by the chemical combination of two or more elements in definite proportions. A molecule is the smallest unit of most compounds
    27. 27. 5. How do Van der Waals forces hold molecules together? When the sharing of electrons are unequal, a molecule has regions that are charged. An attraction can occur between oppositely charged regions of nearby molecules
    28. 28. 6. How are ionic bonds and Van der Waals forces similar? How are they different? In both cases, particles are held together by attractions between opposite charges. The difference is that ionic charges are stronger
    29. 29. Section 2: Properties of Water
    30. 30. Objectives• Why are water molecules polar?• What are acidic solutions? What are basic solutions?
    31. 31. The Big Idea• Much of our planet is covered in water• Water is necessary for life to exist• If life exists on other planets, there most likely is water present• Water has many properties that make life possible
    32. 32. Polarity (-) The oxygen atom has a stronger attraction for electrons (+)
    33. 33. Hydrogen Bonds• Because of waters partial charges, they can attract each other and create hydrogen bonds• Not as strong as covalent or ionic bonds• Waters ability to create multiple hydrogen bonds gives it many special properties
    34. 34. Cohesion• Attraction between molecules of the same substance
    35. 35. Adhesion• Attraction molecules of different substances
    36. 36. Mixture• Material composed of two or more elements or compounds that are physically mixed but not chemically combined• Ex.) salt & pepper, earths atmosphere
    37. 37. Solutions• Mixture of two or more substances in which the molecules are evenly distributed• Ex.) salt water• Settles out over time
    38. 38. Solutions Cl- Cl- Na+ Na+ WaterWater
    39. 39. Solute• Substance that is dissolved• Ex.) salt
    40. 40. Solvent• The substance that does the dissolving• Ex.) Water
    41. 41. Suspensions• Mixture of water and non- dissolved materials• Ex.) sugar solution, blood• Separate into pieces so small, they never settle out
    42. 42. The pH scale• Indicated the concentration of hydrogen ions in a solution
    43. 43. AcidNeutral Base
    44. 44. Acids• Any compound that forms H+ (hydrogen) ions in solution
    45. 45. Base• A compound that produces OH- (hydroxide) ions in solution
    46. 46. Buffers• Weak acids or bases that can react with strong acids or bases to prevent sharp, sudden pH changes
    47. 47. Homework
    48. 48. 1. Use the structure of a water molecule to explain why its polar Oxygen atom has greater attraction for electrons, therefore the oxygen atom is negative and the hydrogen end is positive
    49. 49. 2. Compare acidic and basic solutions in terms of their H+ ion and OH- ion concentrations Acid have more H+ ions than OH- ions, and bases have more OH- ions than H+ ions
    50. 50. 3. What is the difference between a solution and a suspension? In a solution, all components are evenly distributed. In a suspension, un-dissolved particles are suspended
    51. 51. 4. What does pH measure? The concentration of H+ ions in a solution5. The strong acid hydrogen floride (HF) can be dissolved in pure water. Will the pH of the solution be greater or less than 7? less than 7
    52. 52. Section 3: Carbon Compounds
    53. 53. Objective• What are the functions of each group of organic compounds?
    54. 54. Interest Grabber Section 2-3 Life’s backbone• Most of the compounds that make up living things contain carbon. In fact, carbon makes up the basic structure, or “backbone,” of these compounds. Each atom of carbon has four electrons in its outer energy level, which makes it possible for each carbon atom to form four bonds with other atoms.• As a result, carbon atoms can form long chains. A huge number of different carbon compounds exist. Each compound has a different structure. For example, carbon chains can be straight or branching. Also, other kinds of atoms can be attached to the carbon chain.
    55. 55. Methane Acetylene Butadiene Benzene Isooctane
    56. 56. Macromolecules “giant molecules”• Formed by a process called polymerization
    57. 57. Monomers• Smaller units
    58. 58. Polymers• Linked up monomers
    59. 59. Carbohydrates• Compounds made up of carbon, hydrogen, and oxygen atoms usually in a ratio of 1:2:1• Main source of energy• The monomers of starch are sugars
    60. 60. • Single sugar molecules are called monosaccharides• The large macromolecules formed from monosaccharides are known as polysaccharides
    61. 61. Starch Glucose
    62. 62. Lipids• Made mostly from carbon and hydrogen atoms• Used to store energy
    63. 63. Lipid GlycerolFatty Acids
    64. 64. Proteins• Macromolecules that contain nitrogen as well as carbon, hydrogen, and oxygen• Proteins are polymers of molecules called amino acids
    65. 65. Amino Acids Carboxyl groupGeneral structure Alanine Serine
    66. 66. • More than 20 different amino acids, can join to any other amino acid• The instructions for arranging amino acids into many different proteins are stored in DNA• Each protein has a specific role• The shape of proteins can be very important
    67. 67. ProteinsAminoAcids
    68. 68. Nucleic Acids• Macromolecules containing hydrogen, oxygen, nitrogen, carbon, and phosphorus Double Helix
    69. 69. Nucleotides • Consists of 3 parts: 5-carbon sugar, phosphate group and nitrogen base Nitrogen BasePhosphategroup 5-Carbon Sugar
    70. 70. 2 kinds of nucleic acids• RNA (ribonucleic acids) – contains sugar ribose• DNA (deoxyribonucleic acid) – contains sugar deoxyribose
    71. 71. Homework
    72. 72. 1. Name four groups of organic compounds found in living things carbohydrate, lipid, protein, nucleic acids2. Describe at least one function of each group of organic compounds carbohydrates – energy lipids – store energy proteins – form tissue nucleic acids – transmit hereditary information
    73. 73. 3. Compare the structures and functions of lipids and starches Lipids are made from carbon and hydrogen. Starches are made of carbon, hydrogen and oxygen. They both can be used to store energy
    74. 74. Section 4: ChemicalReactions and Enzymes
    75. 75. Objectives• What happens to chemical bonds during chemical reactions?• How do energy changes affect whether a chemical reaction will occur?• Why are enzymes important to living things?
    76. 76. The Big Idea• Living things are made up of chemical compounds• Everything that happens to an organism is based on chemical reactions
    77. 77. Chemical Reactions• A process that changes or transforms one set of chemicals into another
    78. 78. Reactants• Elements or compounds that enter into a reaction
    79. 79. Products• Elements or compounds produced by a chemical reaction
    80. 80. Example Reaction: Getting rid of carbon dioxide • In the bloodCO2 + H20  H2CO3 (carbonic acid) • In the lungsH2CO3  CO2 + H2O Released as you breathe
    81. 81. Energy in reactions Energy-Absorbing Reaction Energy-Releasing Reaction Products Activation energy Activation energy ReactantsReactants Products
    82. 82. Activation Energy• The energy that is needed to get a reaction started
    83. 83. Enzymes• Some chemical reactions are too slow or have activation energies that are too high to make them practical for living tissue• These chemical reactions are made possible by catalysts
    84. 84. Catalyst• Substance that speeds up the rate of chemical reactions• Work by lowering a reactions activation energy
    85. 85. Enzyme• Biological catalysts• Speed up reactions in cells• Very specific• Named for the reaction is catylzes• Enzyme names always end in -ase
    86. 86. Reaction pathwaywithout enzyme Activation energy without enzymeReactants Activation energy Reaction pathway with enzyme with enzyme Products
    87. 87. Substrates• The reactants of enzyme catalyzed reactions• The active site of the enzyme and the substrate have complementary shapes• Fit like a lock and key
    88. 88. Enzyme Action Enzyme – substrate complex
    89. 89. Enzyme ADP (hexokinase) Glucose SubstratesProducts ATP Glucose-6- phosphate Products Active site are released Substrates Enzyme-substrate bind to complex enzyme Substrates are converted into products
    90. 90. Regulation of Enzyme Activity• Enzymes are affected by any variable that affects chemical reactions1. pH2. Temperature3. Concentration of enzyme
    91. 91. Homework
    92. 92. 1. What happens to chemical bonds during chemical reactions Bonds are broken in reactants and new bonds are formed in products2. Describe the role of energy in chemical reactions some chemical reactions release energy, and other chemical reactions absorb energy. Energy changes determine how easily a chemical reaction will occur
    93. 93. 3. What are enzymes, and how are they important to living things? Enzymes are biological catylasts. Cells use enzymes to speed up virtually every important chemical reaction that takes place in cells
    94. 94. 4. Describe how enzymes work, including the role of the enzyme substrate complex Substrates, the reactants of an enzyme-catylzed reaction, attach to the enzyme at an active site and form an enzyme – substrate complex. Once the complex is formed, the enzyme helps convert substrate into product
    95. 95. 5. A change in pH can change the protein. How might a change in pH affect the function of an enzyme such as hexokinase (hint: think about the analogy of the lock and key) A change in pH could change the shape of hexokinase. This change would diminish the ability of glucose and ATP to bind to the active site of the enzyme.

    ×