Aerobic Respiration Textbook pages 106 107 Aerobic requires

Aerobic Respiration Textbook pages 106 -107

Aerobic • requires oxygen – oxygen is required for the remainder of cellular respiration

Krebs Cycle • process where pyruvic acid is broken down into CO 2 in a series of energy-extracting reactions • named after Hans Krebs • also called the Citric Acid Cycle

Krebs Cycle • occurs in mitochondria • only produces 2 ATP molecules – but produces a lot of high energy e– e- get stored on NADH and FADH 2

• • Krebs Cycle Reactants pyruvic acid (also called pyruvate) NAD+ FAD (similar to NAD+ - it is an electron carrier) ADP

• • CO 2 NADH FADH 2 ATP Krebs Cycle Products

38 ADP +38 P C 6 H 12 O 6 + 6 O 2 6 CO 2 + 6 H 2 O + energy CELL WORK 38 ATP

Electron Transport Chain • uses the high-energy electrons from the Krebs cycle to convert ADP into ATP • occurs in inner mitochondria membranes

Electron Transport Chain • series of proteins that pass electrons • movement of e- = ENERGY • causes H+ ions to cross the membrane

Electron Transport Chain • last protein is an enzyme that combines electrons with H+ and O 2 to form H 2 O • H+ ions pass through ATP synthase back into the inner membrane by diffusion to produce ATP

ATP Production of ETC • produces a maximum of 34 ATP molecules per molecule of glucose – this number can vary and is still being studied

ETC Reactants • • NADH – from Krebs cycle FADH 2 – from Krebs cycle ADP O 2

ETC Products • • NAD+ FAD ATP H 2 O

Overall ATP Production • 38 ATP molecules • ATP supply in cells can get used up in a few seconds – must be constantly regenerated

Energy Loss as Heat • less than half of the total energy in glucose is transferred to ATP molecules – the rest of the energy from glucose is released as HEAT