Cellular Respiration

The controlled release of energy in the form of ATP

Emily Kennedy 3A

Step 1: Glycolysis• Glycolysis – splitting of one 6-carbon

sugar (glucose) to two 3-carbon

sugars (pyruvate)

• The 3-carbons are oxidized to

pyruvate

• Takes place in cytoplasm

• Oxygen is not required for glycolysis

– therefore it is ANAEROBIC

• 2 ATP are invested, and 4 are

produced, so there is a 2 ATP NET

YIELD

Step 1: Glycolysis Products

Overall Products• 2 Pyruvate• 2 ATP• 2 NADH• 2 H+• 2 H2O

NAD+ is reduced to NADH

• http://www.sumanasinc.com/webcontent/animations/content/cellularrespiration.html

Remember the number 2!

Step 2: Oxidative Decarboxylaton(Link Reaction)

• This is the step between glycolysis and

the Kreb’s cycle

• Oxygen is needed

• Pyruvate gets converted into Acetyl

CoA after attaching to the coenzyme

• One carbon is taken out for CO2, thus

leaving only 2 carbons left

• Occurs in the mitochondria

Acetyl CoA + CO2 + NADH + H+

Step 2: Oxidative Decarboxylaton Products

Overall Products• 2 Acetyl CoA• 2 CO2• 2 NADH + H+

Step 3: The Kreb’s CycleKreb’s cycle - metabolic process that

completes the breakdown of glucose

• Requires oxygen

• The 2-carbon Acetyl CoA attaches to

4-carbon oxyloacetate

Products• 2 ATP

• 6 NADH + H+

• 2 FADH2

• 2 CO2

• http://www.sumanasinc.com/webco

ntent/animations/content/cellularres

piration.html

Step 4: Oxidative Phosphorylation and the Electron Transport Chain

Step 4: Oxidative Phosphorylation and the Electron Transport Chain

ETC is a series of electron carriers located in the inner membrane of the mitochondria

– made of mostly proteins

• Occurs in the inner membrane

• NADH/FADH molecules donate electrons who use their energy to help proteins

pump H+ protons across the membrane – reverse concentration gradient

• Oxygen grabs dead electrons at the end of ETC, combining with H+ to make water

• H+ protons flow across membrane due to concentration gradient

• ATP synthase serves as a filter and converts ADP + Pi + H+ to ATP

• If lack of O2, gradient will disappear, stopping ATP production

• http://www.sumanasinc.com/webcontent/animations/content/cellularrespiration

.html

Step 4: Oxidative PhosphorylationProducts

• When H+ flows through the ATP synthase into the matrix, 34

ATP is produced

Total ATP = 38 ATP per glucose