- All organisms need energy from food. Cell Respiration - All organisms need energy from food. They obtain this energy through a process called cellular respiration. This is glucose! It’s food! It’s organic!

- When an organism makes energy, It is in the form of a molecule called ATP

ADP + P + energy ATP - ATP is made from a molecule of ADP and a Phosphate, with the help of energy released from glucose. - ATP can be broken back into ADP and Phosphate to release the Energy to do cell work.

There are two types of respiration:

Anaerobic (fermentation): uses no oxygen and produces a little energy (2ATP) from glucose. This starts with a process called glycolysis, where a glucose is partially broken down to gain 2 ATP (this occurs in the cytoplasm.) C6H12O6 + 2 ATP 2 pyruvic acid + 4 ATP (start-up energy) (a 3 C compound) (a gain of 2 ATP)

Some organisms take the pyruvic acid and break it down into waste products to be excreted: Bacteria and yeast mammal muscle cells Turns pyruvic acid Into alcohol and CO2 Turns pyruvic acid Into lactic acid Both processes yield/make 2 ATP Without the use of O2

2. Aerobic cellular respiration: uses oxygen and produces a lot of energy (36 ATP) from glucose (the oxygen helps to completely break down the glucose.) Occurs in the mitochondria. Overall reaction for aerobic respiration:

First, glycolysis occurs and yields 2 pyruvic acid and 2 ATP. Then, Oxygen is used to completely Break down the pyruvic acid and make CO2, H2O as wastes and 34 more ATP This is much more efficient than anaerobic respiration because 36 ATP are produced in total.

There are 2 processes involved in extracting all of the energy from pyruvic acid aerobically: Krebs Cycle Electron Transport Chain

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