1. Cellular Respiration – A Review of the Process
AP BIO

2. Glycolysis Breaks down glucose into pyruvic acid 2 ATP are added
2 NADH are produced by NAD+ accepting 2 electrons
4 ATP are produced (yielding a net gain of 2 ATP)
2 Pyruvic acid molecules are formed
**There are 9 intermediate molecules between glucose and pyruvate**

3. Krebs Cycle (Citric Acid Cycle)
Before the actual cycle begins, pyruvate combines with coenzyme A (CoA) to produce a molecule called acetyl CoA
1 NADH and 1 CO2 is produced
The first actual step of the Krebs Cycle is when oxaloacetate combines with acetyl CoA to make citric acid
Products: 3 NADH, 1 FADH2, 1 ATP 2CO2 (this is the CO2 that we exhale)

4. Oxidative Phosphorylation
The process of extracting ATP from NADH and FADH2
Electrons from the carriers are passed down an ETC
The electrons final acceptor is an Oxygen molecule, and water is formed as a byproduct
NADH can produce 3 ATP
FADH2 can produce 2 ATP

5. Chemiosmotic Phosphorylation
When the electrons lose energy in O.P. it is used for chemiosmotic phosphorylation
As the carriers move through the ETC, H+ are pumped from the matrix, across the cristae, and into the outer compartment creating a proton gradient (Potential Energy Reservoir)
Channel proteins (ATP Synthase) in the cristae allow the protons to flow through and use the energy to produce ATP from ADP

7. 2 Types of Phosphorylation
Substrate Level – Occurs when a phosphate group and its energy is transferred to ADP to form ATP. The substrate molecule donates the phosphate (occurs in glycolysis)
Oxidative Phosphorylation – Occurs when phosphate is transferred but not the energy. Energy is provided from electrons in the ETC

8. Alcoholic Fermentation
Pyruvic Acid is converted into acetaldehyde
1 CO2 and 1 acetaldehyde is produced
Acetaldehyde is converted into ethanol
1 ethanol is produced, and 1 NAD+ is produce
The entire point of this process is to send NAD+ back to glycolysis to keep slowly producing ATP

9. Lactic Acid Fermentation
Pyruvic Acid is converted to lactic acid
NAD+ is given off and sent back to glycolysis