Cellular Respiration Adenosine Triphosphate (ATP) is the basic energy source of all cells.

Sunlight is the ultimate source of energy for life Sunlight is the ultimate source of energy for life. However, it is an unusable form of energy. Photosynthesis converts light energy into the chemical energy of carbohydrates and glucose

Glucose has energy stored in the bonds, but it has to be released Respiration conversts the energy in glucose to ATP, which is the cell’s only usable energy source

Cellular Respiration Cellular respiration is the process of breaking down glucose to release energy for ATP Where does this occur?

Steps of Cellular Respiration Glycolysis – one molecule of glucose is split into two pyruvic acid Net gain of 2 ATP molecules

Steps of Cellular Respiration AEROBIC RESPIRATION– occurs after glycolysis if oxygen is present ANAEROBIC RESPIRATION (Fermentation) occurs after glycolysis if oxygen is not present Kreb’s Cycle – pyruvic acid is broken down and carbon dioxide is released Electron Transport Chain – uses high energy electrons to produce ATP Produces a total of 34 ATP Alcoholic Fermentation – forms ethyl alcohol and carbon dioxide as waste Ex: yeast, makes bread rise Lactic Acid Fermentation – forms lactic acid Ex: bacteria, used for dairy products and this is why your muscles are sore after exercising

ATP Photosynthesis Cellular Respiration

The ATP Cycle The energy in the ATP molecule is released by breaking the bond between the 2nd and 3rd phosphate groups. This results in the molecule Adenosine Diphosphate (ADP). The ADP and 3rd phosphate group is then recycled to be used in the production of more ATP. ATP +P -P ADP