Oh where, Oh where

has 34molecules of ATP

gone????????

Only the Krebs cycle knows for

sure.

The energy produced from the "burning" of glucose is used to make ATP. In chemistry this process is called the oxidation of glucose. The purpose of cellular respiration is to make ATP. All cells use and need ATP.

There are 3 parts to cellular respiration

3 Part of Respiration

I. Glycolysis

II. Kreb's Cycle

III. Electron Transport Chain

After glycolysis, pyruvic acid is shuttled to the mitochondrion to extract the energy from this molecule and convert it to ATP. This is done by stripping the remaining hydrogens from pyruvic acid or pyruvate. There are two molecules of pyruvic acid so the Kreb's cycle occurs twice. The hydrogens are used to reduce NAD and FAD. In addition 3 molecules of carbon dioxide are released. The Kreb’s cycle is located in the inner compartment of the mitochondrion.

Summary of Krebs- Occurs in mitochondrion

2X’s

Pyruvate---> 3 CO2 6 CO2

1 ADP ---> 1 ATP 2 ATP

4 NAD ---> 4 NADH2 8 NADH2

1 FAD ---> 1 FADH2 2 FADH2

The hydrogen found on pyruvate will be used to reduce NAD and FAD. Only one ADP is phosphorylated at the substrate level or directly by enzymes.

Step 1

Prepping step. Pyruvate is decarboxy-lated and also oxidized. The hydrogens are used to reduced NAD. Technically not a part of the Kreb’s cycle

Step 2

The acetyl group is attached to oxaloacetic acid to form citric acid

Prepping part-

Technically not an official step of the Kreb’s cycle

Step 2

Technically not an official step of the Kreb’s cycle

Step 3

Water is removed and then added back in to make isocitric acid

Step 4

Isocitric acid will be oxidized and NAD will be-come reduced. The new acid is oxalosuccinic acid

Steps 3 and 4

Citric acid is isomerizes to make isocitric acid and then isocitric acid is oxidized making oxaloacetic acid. This step reduces NAD

Step 5 Oxalosuccinic acid will be decarboxylated as it is converted to a-ketoglutaric acid. It now has only 5 carbons. Second CO2 is released.

Step 6 -a ketoglutaric acid will be decarboxylated and at the same time oxidized. NAD will be reduced. Third CO2 is released.

Step 5 Oxalosuccinic acid will be decarboxylated as it is converted to a-ketoglutaric acid. It now has only 5 carbons. Second CO2 is released.

Step 6 -a ketoglutaric acid will be decarboxylated and at the same time oxidized. NAD will be reduced. Third CO2 is released.

Step 7. The next step is rather complicated. Succinyl-Co-A looses the coenzyme Co-A and is hydrated. Phosphate is added to GDP--->GTP which in turns takes the phosphate and gives it to ADP--->ATP.

Step 8. Succinic acid becomes oxidized and FAD becomes reduced.

Step 7. The next step is rather complicated. Succinyl-Co-A looses the coenzyme Co-A and is hydrated. Phosphate is added to GDP--->GTP which in turns takes the phosphate and gives it to ADP--->ATP. This is known as substrate phosphorylation.

Step 8. Succinic acid becomes oxidized and FAD becomes reduced.

Step 9. Fumaric acid becomes hydrated as water is added to it.

Step 10.

The last step malic acid is oxidized and NAD is reduced to return to oxaloacetic acid and start the cycle again

Step 9. Fumaric acid becomes hydrated as water is added to it.

Step 10. The last step malic acid is oxidized and NAD is reduced to return to oxaloacetic acid and start the cycle again

Summary of Krebs- Occurs in mitochondrion

2X’s

Pyruvate---> 3 CO2 6 CO2

1 ADP ---> 1 ATP 2 ATP

4 NAD ---> 4 NADH2 8 NADH2

1 FAD ---> 1 FADH2 2 FADH2

The hydrogen found on pyruvate will be used to reduce NAD and FAD. Only one ADP is phosphorylated at the substrate level or directly by enzymes.

The purpose of chemiosmosis is to extract the energy found in NADH and FADH2 to make more ATP. This involves the cristae. There are electron transport chains that are used.

The electrons from the NADH and FADH2 are used to move on the electron transport chain. As the electrons move down the electron transport chain, H+ ions are pumped across the membrane.

The electrons from one NADH can pump 6 H+ across the membrane, but the electrons from FADH2 can only pump 4 H+ across the membrane.

The outer compartment of the mitochondria becomes positive and the inside becomes negative like a battery. This "battery" can do work. The hydrogen ions can cross an F1 particle and make ATP.

It takes 2 H+ to cross the F1 particle to provide enough energy to make ATP. Because the electron transport chain oxidizes NADH or FADH2 and uses the energy to phosphorylate ADP, this is also known as oxidative phosphorylation.

8 NADH2 x 6 H = 48 H+

2 FADH2(Krebs)x 4 H = 8 H+

2 FADH2(glyc.) X 4 H = 8 H+ ATP Summary

64 H+ 64 H+ --> 32 ATP

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ATP can be made from other foods other than glucose.

I. Carbohydrates

a. Starch--> X's glucose molecules and now respired in glycolysis

b. Sucrose--> glucose and fructose and now respired in glycolysis

II. Fats/Lipids-> Glycerol and 3 fatty acids

Glycerol is converted to PGAL and respired in glycolysis.

The fatty acids are chopped into 2 carbon acetyl groups and used in the Krebs or citric acid cycle.

III. Proteins--> amino acids

Once the amino acids are produced, then the

amine group must be removed. The left over

acid is then used at some point in the Krebs cycle