Cellular Respiration Chapter 6

What you need to know! The role of glycolysis in oxidizing glucose to two molecules of pyruvate. The process that brings pyruvate from the cytoplasm into the mitochondria and introduces it into the citric acid cycle. How the process of chemiosmosis utilizes the electrons from NADH and FADH2 to produce ATP.

Aerobic Cellular Respiration Definition: getting chemical bond energy from glucose molecules Redox reaction that: Reduces O2 to H2O Oxidizes glucose to CO2 Animal and plant cells Location: cytoplasm and mitochondria Utilizes NAD & FAD as electron carriers (energy) Rx: 6O2 + C6H12O6 → 6 CO2 + 6 H20 + 38 ATP

Anatomy of a Mitochondrion

3 Stages of Cellular Respiration Glycolysis Citric Acid Cycle (Krebs Cycle) Oxidative Phosphorylation

ATP Yield Glycolysis = 2 ATP Citric Acid Cycle = 2 ATP (1 per cycle) Yields 4 ATP Costs 2 ATP Citric Acid Cycle = 2 ATP (1 per cycle) Oxidative Phosphorylation = 34 ATP Total = ATP

The Big Picture

Biology Crash Course http://www.youtube.com/watch?v=00jbG_cfGuQ This video will function as an excellent review of the concepts

BIG IDEA Glycolysis and citric acid cycle produce a small amount of ATP and (more importantly) molecules of NADH and FADH2 (carry electrons to the ETC). Oxidative phosphorylation uses electrons from NADH and FADH2 for the ETC, which makes a ton of ATP

1. Glycolysis Location: cytoplasm Breaking down glucose into 2 pyruvate Needs 2 ATP as activation energy Subsequent enzyme Rx’s produce 4 ATP Glucose is converted into 2 pyruvate with a net yield of 2ATP & 2 NADH No O2 is needed

1. Glycolysis

Preparatory Step in Mitochondria (directly before Citric Acid Cycle) Both Pyruvic acids are turned into Acetyl CoA by The attachment of CoA, releasing one carbon as CO2 Formation of 2 NADH

2. Citric Acid Cycle (Krebs Cycle) Location: mitochondria No oxygen required 2 cycles (one for each pyruvate)

2. Citric Acid Cycle (Krebs Cycle) Each cycle produces: Releasing 2 carbons as CO2 Production of 1 ATP Production of 3 NADH Production of 1 FADH2 Total Yield: Do the math and write it down

2. Citric Acid Cycle (Krebs Cycle)

3. Oxidative Phosphorylation Location = mitochondria: intermembrane space, inner mitochondrial membrane, matrix Oxygen needed 2 Parts: Electron Transport Chain (ETC): row of interconnected membrane bound transport proteins & electron carriers Accepts electrons from NADH & FADH2 Creates H+ gradient Oxygen & H+ binds to electrons at the end to make water

3. Oxidative Phosphorylation

3. Oxidative Phosphorylation Chemiosmosis: ATPsynthase imbedded in the membrane allows the flow of H+ into the cell Produces 34 ATP Provides the H+ to make water at the end of the ETC

Oxidative Phosphorylation

Oxidative Phosphorylation

The Big Picture