B-3.2: Summarize the basic aerobic and anaerobic processes of cellular respiration and interpret the chemical equation for cellular respiration

  Convert chemical energy in nutrients to chemical energy stored in ATP  ATP can then be used for energy for:  Cellular metabolic processes  Active transport across cell membrane  Protein synthesis  Muscle contraction (exercise)  Any organic compound (food) can be processed and broken down as a source of energy to produce ATP  Nutrients + oxygen  water + energy (ATP) + carbon dioxide What is Cellular Respiration?

  Glycolysis  A glucose molecule is broken down into:  Pyruvic acid molecules  ATP molecules  Glycolysis is a series of reactions using enzymes  Occurs in the cytoplasm 1 st stage of Cellular Respiration

  When oxygen is available, the 2 nd step is the two step process of aerobic respiration, occurs in mitochondria  1 st step: Citric acid or Krebs cycle  2 nd step: Electron transport chain 2 nd step of Cellular Respiration

  First step of aerobic respiration is citric acid or Krebs cycle  Uses the pyruvic acid formed in glycolysis  A series of steps, releasing carbon dioxide, water, and energy  Pyruvic acid  CO 2 + H 2 O + energy (2 ATP) Aerobic Respiration – part 1

  2 nd step of aerobic respiration = electron transport chain  Most of the ATP is formed during this part  Series of chemical reactions ending with hydrogen combining with oxygen to form water. Carbon dioxide is released as a waste product as it is formed in several stages of the Krebs cycle  Each reaction produces a small amount of energy  By the end of the cycle, it produces up to 36 ATP molecules  Any ATP made is used by the cell for cellular metabolism Aerobic Respiration – part 2

  C 6 H 12 O 6 + 6O 2  6CO 2 + 6H energy  In words,  1 glucose molecule and 6 oxygen molecules produce 6 carbon dioxide molecules and 6 water molecules  Each reactant is used during different stages of aerobic respiration  Each product is formed during different stages of the process  Produce about 34 to 36 ATP molecules per 1 glucose molecule Aerobic respiration

  What happens if there is no oxygen available?  Anaerobic respiration occurs aka fermentation No oxygen?