3.7 Cellular Respiration Cellular respiration is the controlled release of energy from organic compounds (lipids, carbohydrates and proteins) in cells to produce ATP.

3.7 Syllabus Statements Define ‘Cellular Respiration State that, in cell respiration, glucose in the cytoplasm is broken down by glycolysis into pyruvate, with a small yield of ATP Explain that, during anaerobic cell respiration, pyruvate can be converted in the cytoplasm into lactate, or ethanol and carbon dioxide, with no further yield of ATP Explain that, during aerobic cell respiration, pyruvate can be broken down in the mitochondrion into carbon dioxide & water with a large yield of ATP.

Cellular Respiration (The Basics) Cellular respiration is the controlled release of energy from organic compounds (lipids, carbohydrates and protein) in cells to form ATP. Occurs in ALL ORGANISMS (even those organisms like prokaryotes w/out mitochondria) because all living cells need a continual supply of energy. Cellular respiration is considered a catabolic reaction and involves a series of very complex metabolic reactions involving numerous enzymes.

Cellular Respiration Involves a Transformation of Energy.

The Balanced Equation

Cellular Respiration and Breathing (Respiration) Cellular Respiration occurs at the cellular level and is NOT the same thing as breathing. Cellular Respiration occurs at the cellular level (cytoplasm and mitochondrion in eukaryotes) and inner cell membrane (prokaryotes). Breathing delivers a reactant (oxygen gas) for cell respiration and removes a waste product (carbon dioxide).

Where Does Cellular Respiration Occur? In prokaryotes, however, cell Respiration occurs in the folds of the Cell membrane.

A Summary of Aerobic Cell Respiration In aerobic cell respiration, approx ATP are produced per glucose Molecule.

The Use of Glucose in Cell Respiration Glucose is often the organic compound used in cell respiration. Chemical reactions in the cytoplasm break down glucose into a simpler organic compound called pyruvate. A small amount of ATP is released.

Anaerobic Cell Respiration If no oxygen is available, the pyruvate remains in the cytoplasm and is converted into a waste product that can be removed from the cell. No ATP is produced in these reaction. In humans, the waste product lactate (lactic acid) is produced. In yeast, the products are ethanol (alcohol) and carbon dioxide.

Aerobic Cell Respiration If oxygen is available, the pyruvate enters the mitochondrion. Inside the mitochondrion, the pyruvate is broken down into carbon dioxide and water. A large amount of ATP (36-38 ATP molecules) are produced from one glucose molecule. Aerobic cell respiration has a higher yield (per gram of glucose) than anaerobic cell respiration.

SUMMARY

Comparing Photosynthesis and Cellular Respiration

Interpreting Graphs