part2

• Adenosine triphosphate (ATP)


  A molecule consisting of adenosine bonded to three phosphates, with a large amount of energy packed into the phosphate bonds
• Energy cannot be created or destroyed, the sum of energy in the universe is constant (first law of thermodynamics)
• Energy transfer leads to less organization, the universe tends toward disorder (second law of thermodynamics)
• Organisms require energy for almost everything they do
• ATP


  Allows cells to acquire the energy they need without becoming a major mess
• Sources of ATP


  1. Photosynthesis

  2. Cellular respiration
• Photosynthesis


  • Transformation of solar energy into chemical energy
  • Plants use their leaves to capture sunlight and make glucose
• Photosynthesis


  1. Light reaction (light-dependent reaction)

  2. Dark reaction (light-independent reaction)
• Light reaction


  Activated chlorophyll molecule passes excited electrons down to a series of light dependent reactions and light independent reactions, ultimately producing ATP and NADPH
• Dark reaction


  Uses ATP, NADPH, and carbon dioxide to make carbohydrates
• The whole point of the light reaction is to produce energy in the form of ATP and electron carriers, specifically NADPH
• C6H12O6 + 6O2 -> 6CO2 + 6H2O + ATP
• Aerobic respiration


  ATP is made in the presence of oxygen
• Anaerobic respiration


  ATP is made without the presence of oxygen
• When you exercise


  Your muscles require a lot of energy
• As you continue to exercise

  Your body doesn't get enough oxygen to keep up with the demand in your muscles, creating an oxygen debt
• Anaerobic respiration in muscle cells

  Pyruvic acid produced from glycolysis is converted to lactic acid
• Lactic acid buildup


  Causes your muscles to ache