Cellular Respiration Glycolysis, Krebs cycle, Electron Transport

The term cellular respiration is an oxidation-reduction process in which organic food is broken-down inside the cell and energy is released, Hence it is the form of catabolic process.
Cellular respiration includes both aerobic and anaerobic processes. Cellular respiration is a multi step process of breakdown of glucose to release energy.These include glycolysis, the preparatory reaction, the citric acid cycle, and the electron transport chain. ATP production is also discussed.The word glycolysis means “sugar splitting,” and that is
exactly what happens during this pathway. Glucose, a sixcarbon
sugar, is split into two three-carbon sugars.

1. botany

2. ASSIGNMENT TOPIC: RESPIRATION ITS TYPES & CYCLES

3. CONTENTS: DEFINATION OF RESPIRATION TYPES OF RESPIRATION CYCLES OF AEROBIC RESPIRATION GLYCOLYSIS KREBS CYCLE ELECTRON TRANSPORT CHAIN OXIDATIVE PHOSPHORYLATION ENEGY BALANCE OF RESPIRATION

4. RESPIRATION: RESPIRATION IS ALSO CALLED CELLULAR RESPIRATION. IT IS THE PROCESS OF BREAKING OF SUGAR INTO A FORM THAT THE CELL CAN USE AS ENEGY IS CALLED CELLULAR RESPIRATION. EQUATION

5. Types: THERE ARE TWO MAIN TYPES OF RESPIRATION WHICH ARE; AEROBIC RESPIRATION ANAEROBIC RESPIRATION

6. AEROBIC RESPIRATION: RESPIRATION WHICH OCCURS IN THE PRESENCE OF OXYGEN TO PRODUCE ATP IS CALLED AEROBIC RESPIRATION. EQUATION:

7. STAGES OF AEROBIC RESPIRATION: THERE ARE FOUR STAGES OF AEROBIC RESPIRATION WHICH ARE FOLLOWING: GLYCOLYSIS LINK REACTIONS KREBS CYCLE OR CITRIC ACID CYCLE ELECTRON TRANSPORT CHAIN (ETC)

8. GLYCOLYSIS: THE PROCESS OF BREAKDOWN OF GLUCOSE IN THE CYTOPLASM INTO TWO MOLECULES OF PYRUVATE IS CALLED GLYCOLYSIS.TEN ENZYMES ARE NEEDED FOR THE TEN INTERMEDIATE COMPOUND IN THIS PROCESS.

9. STEPS OF GLYCOLYSIS: THERE ARE FOUR STEPS OF GLYCOLYSIS: TWO ENERGY RICH ATP KICK START THE PROCESS AT THE END ARE TWO PYRUVATE MOLECULES.FOUR MOLECULES OF ATP ARE MADE AND TWO NADH MOLECULES. BOTH TYPES ARE ENERGY RICH AND USED IN OTHER CELL REACTIONS. IN CELLS WHICH USE OXYGEN,THE PYRUVATE IS USED IN A SECOND PROCESS, THE KREBS CYCLE,WHICH PRODUCES MORE ATP MOLECULES.

10. In cells which use oxygen , the pyruvate is used in a second process, the krebs cycle , which produces more atp molecules.

11. LINK REACTIONS: IN THIS STAGE PYRUVATE FROM GLYCOLYSIS IS ACTIVELY PUMPED INTO MITOCHONDRIA .ONE CARBON DIOXIDE MOLECULE AND ONE HYDROGEN MOLECULE ARE REMOVED FROM THE PYRUVATE CALLED OXIDATIVE DECARBOXYLATION TO PRODUCE AND ACETYL GROUP , WHICH JOINS TO AN ENZYME CALLED CoA TO FORM ACETYL CoA . THIS IS ESSENTIAL FOR THE KREBS CYCLE.

12. KREBS CYCLE: KREBS CYCLE IS ALSO CALLED CITRIC ACID CYCLE . IN THIS STAGE PYRUVIC ACID BREAKS DOWN INTO CARBON DIOXIDE IN THE PRESENCE OF OXYGEN IN MITOCHONDRIA. OR THIS IS ALSO CALLED TRICARBOXYLIC ACID CYCLE .

13. STEPS: WHEN OXYGEN IS PRESENT ACETYL CoA IS PRODUCED FROM THE PYRUVATE MOLECULE CREATED FROM GLYCOLYSIS. ONCE ACETYL CoA IS FORMED AEROBIC OR ANAEROBIC RESPIRATION CAN OCCUR. WHEN OXYGEN IS PRESENT THE MITOCHONDRIA WILL UNDERGO AEROBIC RESPIRATION WHICH LEADS TO THE KREBS CYCLE. IF OXYGEN IS NOT PRESENT FERMENTATION OF THE PYRUVATE MOLECULE WILL OCCUR. IN THE AEROBIC RESPIRATION WHEN ACETYL CoA IS PRODUCED FROM THE PYRUVATE MOLECULE IS OXIDIZED TO CO(2) CARBON DIOXIDE WHILE AT THE SAME TIME IT REDUCING NAD TO NADH.

14. THEN NADH CAN BE USED BY THE ELECTRON TRANSPORT CHAIN TO CREATE FURTHER ATP ASPART OF OXIDATIVE PHOSPHORYLATION . TO FULLY OXIDIZED THE EQUIVALENT OF ONE GLUCOSE MOLECULE TWO ACETYLE CoA MUST BE METABOLIZED BY THE KREBS CYCLE. TWO WASTE PRODUCTS H(2)O WATER AND CO(2) CARBON DIOXIDE ARE CREATED DURING THIS CYCLE.

15. ELECTRON TRANSPORT CHAIN: ELETRON TRANSPORT CHAIN IS A SET OF ENZYMES WHICH IS LOCATED ON THE INNER MITOCHONDRIAL MEMBRANE AND MAIN SOURCE OF ENERGY IN AEROBIC PATHWAY OF ENERGY GENERATION.

16. OVERVIEW: THE MITOCHONDRIA HAS: OUTER MITOCHONDRIAL MEMBRANE INNER MITOCHONDRIAL MEMBRANE INTER MEMBRANE SPACE MATRIX OF MITOCHONDRIA THE CLOSE SECTION OF MITOCHONDRIAL MEMBRANE SHOW THE STRUCTURE OF ELECTRON TRANSPORT CHAIN. INNER MITOCHONDRIAL MEMBRANE CONTAIN 4 SETS OF ENZYME COMPLEXES.

17. ETC COMPLEXES: THERE ARE FOUR ELECTRON CHAIN COMPLEXES IN INNER MITOCHONDRIAL MEMBRANE WHICH ARE NAMED AS ROMAN NUMERALS FROM 1 TO 4. COMPLEX I COMPLEX II COMPLEX III COMPLEX IV

18. COMPLEX I: THE FIRST COMPLEX OF ELECTRON TRANSPORT CHAIN IS NAMED AS: NADH DEHYDROGENASE COMPLEX REDUCE FORM OF REMOVES HYDROGEN CONTAIN FMN AND NADH FE-S OR NADH – OXIDO – REDUCTASE FROM OXIDATION-REDUCTION REACTIONS IT IS L-SHAPED PROTEIN COMPLEX. IT CARRY ELECTRONS FROM NADH TO THE SECOND COMPLEX .

19. COMPLEX II: THIS COMPLEX IS NAMED AS: SUCCINATE-DEHYDROGENASE COMPLEX REMOVES HYDROGEN FROM CONTAIN FMN SUCCINATE FE-S IT ALSO A PART OF KREBS CYCLE. IN WHICH SUCCINATE OXIDIZED INTO FUMARATE. FADH2 IS PRODUCED IN THIS REACTION WHICH IS USED FOR DONATION OF ELECTRONS IN THE ELECTRON TRANSPORT CHAIN.FE-S (IRON- SULPHUR) CLUSTERS ARE PRESENT IN THIS COMPLEX.

20. COMPLEX III: IT IS CALLED CYTOCHROME REDUCTASE . IT IS ALSO KNOWN AS Q-CYTOCHROME C OXIDOREDUCTASE . CYTOCHROMES: ARE A GROUP OF PROTEINS WHICH HAVE HEME AS THEIR COMPLEXES AND OTHER PROSTHETIC GROUPS .THEY ALSO CONTAIN IRON CORE ( IN WHICH IRON EXISTS AS OXIDIZE AND REDUCE FORM ) . Fe2+ Fe3+

21. THE THIRD COMPLEX HAS THREE NUMBERS OF CYTOCHROMES: CYTOCHROME B CYTOCHROME C1 CYTOCHROME C CYTOCHROME B AND C1 EXCEPTS ELECTRONS FROM ETC AND TRANSPORT THEM TO CYTOCHROME C WHICH THEN TRANSPORT THESE ELECTRONS TO THE 4 TH COMPLEX.

22. COMPLEX IV: THIS COMPLEX IS NAMED AS: CYTOCHROME C OXIDASE CONTAIN HEME & COPPER UNITS CYTOCHROME C OXIDASE: THIS COMPLEX OXIDIZED THE CYTOCHROME C (CYT C). IT RECEIVES ELECTRONS FROM CYT C AND SEND IT TO COMPLEX IV WHICH USE THESE ELECTRONS FOR REDUCTION OF O2 INTO H2O.THEREFORE IT IS CALLED CYTOCHROME C OXIDASE.

23. CELLULAR RESPIRATION BALANCE SHEET: GLYCOLYSIS-IN CYTOPLASM: 2 ATP FROM SLP( SUBSTRATE-LEVEL PHOSPHORYLATION ) 2 NADH 2 NADH(2) 4 ATP PYRUVATE OXIDATION-MATRIX OF MITOCHONDRIA: 2 NADH 3 ATP ( FROM CHEMIOOSMOSIS ) KREBS CYCLE-MATRIX OF MITOCHONDRIA: 2 ATP FROM SLP 6 NADH 18 ATP ( FROM CHEMIOSMOSIS ) 2 FADH(2) 4 ATP( FROM CHEMIOSMOSIS )

24. ANAEROBIC RESPIRATION: RESPIRATION WHICH OCCURS IN THE ABSENCE OF OXYGEN IN CYTOPLASM AND PRODUCE 2 MOLECULE OF ATP PER GLUCOSE MOLECULE. EQUATION:

25. TYPES: THERE ARE TWO TYPES OF AEROBIC RESPIRATION IN PLANTS: GLYCOLYSIS ( CYTOPLASM ) FERMENTATION SUB-TYPES : ALCOHOLIC FERMENTATION LACTIC ACID FERMENTATION ( CYTOPLASM )

26. FERMENTATION: THE PROCESS IN WHICH DECARBOXYLATES PYRUVATE CONVERT INTO ACETALDEHYDE WHICH IS REDUCED TO ETHANOL.THEN NADH REGENRATE NAD^+ TO CONTINUE GLYCOLYSIS IS CALLED FERMENTATION. EQUATION:

27. EXAMPLE: IT OCCURS IN ANAEROBIC MICROORGSNISMS SUCH AS YEAST . TYPES OF FERMENTATION: ALCOHLIC FERMENTATION: IT TAKES PLACE IN YEAST AND SOME BACTERIA AND YIELDS ONLY THE 2 ATP MOLECULE,PRODUCED IN GLYCOLYSIS. EQUATION:

28. LACTIC ACID FERMENTATION: IT IS A METABOLIC PROCESS BY WHICH GLUCOSE AND OTHER SIX CARBON SUGARS ARE CONVERTED INTO CELLULAR ENERGY AND THE METABOLITE LACTATE,WHICH IS LACTIC ACID IN SOLUTION. EQUATION: EXAMPLE: IT OCCURS IN SOME BACTERIA AND ANIMAL CELLS,SUCH AS MUSCLE CELLS .

29. ENERY BALANCE OF RESPIRATION: ( ATP YIELD PER MOLECULE OF GLUCOSE ) COMPLETE O XIDATION OF GLUCOSE MOLECULE THROUGH GLYCOLYSIS, CONVERSION OF PYRUVIC ACID TO ACETYL CoA AND KREBS CYCLE LEADS TO NET FORMATION OF FOUR MOLECULES OF ATP BY SUBSTRATE LEVEL PHOSPHORYLATION (TWO DURING GLYCOLYSIS AND TWO IN KREBS CYCLE) ; TWO MOLECULES OF NADH2 IN THE CYTOSOL, EIGHT MOLECULES OF NADH2 AND TWO MOLECULES OF FADH2 IN THE MITOCHONDRIAL MATRIX .

30. STEPS OF ENERGY BALANCE: THE OXIDATION OF 8 NADH2 MOLECULES PRODUCED IN MITOCHONDRIAL MATRIX LEAD TO GENERATION OF 24 ATP MOLECULES ; THREE PER NADH2 MOLECULE. FOUR MOLECULES OF ATP ARE GENERATED IN THE OXIDATION OF SUCCINIC ACID TO FUMARIC ACID.THESE MAKE THE TOTAL 28 ATP MOLECULES. ADDITION OF TWO ATP MOLECULES FORMED DURING SUBSTRATE LEVEL PHOSPHOTYLATION IN KREBS CYCLE via GTP BRINGS THE TOTAL ATP SYNTHESIZED TO 30.

31. TWO ATP MOLECULES ARE GENERATED DURING SUBSTRATE LEVEL PHOSPHORYLATION IN GLYCOLYSIS AND FOUR FROM OXIDATION OF NADH2 PRODUCED DURING GLYCOLYSIS. ADDITION OF THESE SIX ATP MOLECULES BRINGS THE TOTAL ATP SYNTHESIS TO 36 MOLECULES. THUS, THERE IS A TOTAL YIELD OF 36 ATP MOLECULES PER GLUCOSE MOLECULE COMPLETELY OXIDIZED TO CO2 AND WATER.

32. OXIDATIVE PHOSPHORYLATION: THE SYNTHESIS OF ATP IN THE PRESENCE OF OXYGEN IS CALLED OXIDATIVE PHOSPHORYLATION. THE BREAKDOWN OF FOOD PRODUCES ATP IN OUR BODY. OXIDATIVE PHOSPHORYLATION: OXYGEN ATP SYNTHESIS OXIDATIVE PHOSPHORYLATION ACCOUNTS FOR A SMALL FRACTION OF ATP GENERATED IN LIVING CELLS OF HIGHER PLANTS.

33. STEPS OF OXIDATIVE PHOSPHORYLATION: THERE ARE THREE STEPS FOR PRODUCTION OF ATP: GLYCOLYSIS PYRUVIC ACID OXIDATION KREBS CYCLE ELECTRON TRANSPORT CHAIN (ETC) OXIDATIVE PHOSPHORYLATION

34. GLYCOLYSIS: THE BREAKDOWN OF GLUCOSE INTO PYRUVIC ACID (3 CARBON MOLECULE) IS CALLED GLYCOLYSIS. PYRUVIC ACID OXIDATION: IN THIS PROCESS THE THREE CARBON MOLECULE OXIDIZED AND GIVE A PROTON WHICH IS CONVERTED INTO TWO CARBON MOLECULE. KREBS CYCLE: TWO CARBON MOLECULE CONVERTED INTO A WATER MOLECULE. THE NADH2 AND FADH2 ARE PRODUCED IN THE KREBS CYCLE AND OXIDIZED TO PRODUCED ATP.

35. PROCESS: THE NUMBER OF ATP MOLECULES SYNTHESIZED DEPENDS UPON THE NATURE OF THE ELECTRON DONOR. ELECTRONS DERIVED FROM OXIDATION OF NADH2 MOLECULE PRODUCED IN THE MATRIX RESULT IN GENERATION OF THREE ATP MOLECULES. FADH2 ENTERS THE RESPIRATORY CHAIN ,ONLY TWO MOLECULES OF ATP ARE GENERATED FOR EACH MOLECULES OF SUCCINIC ACID OXIDIZED TO FUMARIC ACID. THE ATP GENERATION TAKES PLACE AT THREE SITES THAT EXIST ALONG ELECTRON TRANSPORT CHAIN.