6-2 Anaerobic Respiration There are 2 types of respiration: respiration with and without oxygen present. Aerobic respiration occurs with O 2 Anaerobic resp. occurs without O 2 Aerobic resp. produces much more energy than anaerobic

Who does what? Only the unicellular organisms (bacteria mostly) rely solely on anaerobic resp. Everything else can do both anaerobic and aerobic resp. Let’s examine anaerobic resp…

Glycolysis is… …the first step of respiration, which takes place in the cytoplasm of the cell. Um, ok…what’s it mean though? Well, we’ve seen lysis, which means to split. And the glyco refers to glucose, so glycolysis is the splitting of glucose.

Glycolysis continued… Remember, glucose is where we get energy, but glucose must be broken down first… Splitting glucose actually requires energy. The energy to split glucose comes from what molecule with high energy bonds? ATP!!!!

Glycolysis in depth… How many carbons does glucose have? 6! If glucose is split into two equal molecules by ATP (glycolysis), how many carbons will these molecules have? 3! The 3 carbon molecules are called PGAL.

The fate of PGAL… How many PGAL’s does each glucose form? 2 Each PGAL undergoes a series of reactions to form a pyruvic acid (3C) molecule. This process yields 1NADH and 2ATP for each pyruvic acid formed.

The results of glycolysis… So, it takes 2 ATP molecules to split glucose, and then 4 ATP molecules are created when pyruvic acid is formed. How much net ATP is made through glycolysis? 2 NADH is made as well, but it’s energy is only accessible if O 2 is present.

Picture pages… Glucose 2ATP2ADP PGAL Pyruvic Acid 2ADP 2ATP 2ADP2ATP

Anaerobic Respiration If all you do is anaerobic respiration, the only ATP you make is made from glycolysis. Therefore how much ATP do anaerobic organisms make? 2ATP

Post Anaerobic resp… Any reaction that occurs after glycolysis in an anaerobic organism is called fermentation. In fermentation, NADH is oxidized, and pyruvic acid is reduced.

Fermentation… There are 2 types of fermentation we’re going to examine: 1) Lactic acid fermentation 2) Alcoholic fermentation

Lactic Acid Fermentation In lactic acid fermentation, pyruvic acid is converted to lactic acid. Any athletes who have felt muscle burn after a strenuous workout are feeling lactic acid buildup.

Alcoholic Fermentation Some organisms (yeast for example) have enzymes that allow the organism to break pyruvic acid into ethyl alcohol and carbon dioxide. Alcoholic fermentation is important in the process of… breadmaking!!!! (It’s the CO 2 that makes bread rise)

Alcohol again… Of course alcoholic fermentation also gives rise to alcohol… Glucose Source Beverage Barley BEER Potato Vodka GrapesWine Rice Sake