Aerobic respiration - needs oxygen and makes co2, water and 38 ATP

Anaerobic respiration - absence of oxygen, produces lactate (animals) or ethanol and co2 (plants), only 2 ATP created.

Glycolysis - splitting of 6 carbon glucose into 2 x 3 carbon pyruvate

Link reaction - conversion of pyruvate into co2 and 2 carbon acetylcoenzyme A

Krebs cycle - introduction of acetylcoenzyme A into cycle of oxidation - reduction reactions that yield some ATP and many electrons

Electron Transport Chain - use of electrons produced in Krebs cycle to synthesise ATP, h20 as by-product

GLYCOLYSIS

CYTOPLASM
6 CARBON GLUCOSE CONVERTS TO 2X 3 CARBON PYRUVATE

1 - GLUCOSE PHOSPHORYLATED BY ADDITION OF TWO PHOSPHATE MOLECULES THAT COME FROM THE HYDROLYSIS OF 2 X ATP TO ADP. PROVIDES ENERGY TO ACTIVATE GLUCOSE BY LOWERING ACTIVATION ENERGY FOR ENZYME CONTROLLED REACTIONS TO FOLLOW

2 - EACH PHOSPHORYLATED GLUCOSE SPLIT INTO 2 X 3C TRIOSE PHOSPHATE

3 - TP OXIDISED, HYDROGEN REMOVED FROM EACH AND TRANSFERRED TO HYDROGEN CARRIER NAD TO FORM NADH

4 - ATP PRODUCTION - TP CONVERTED TO 3C PYRUVATE X 2.

2 X ATP REGENERATED FROM ADP.

YIELD:

2 X ATP (NET)
2 X NADH
2X PYRUVATE

LINK REACTION

PYRUVATE ACTIVELY TRANSPORTED INTO MITOCHONDRIA MATRIX.

1 - PYRUVATE OXIDISED BY REMOVING HYDROGEN. HYDROGEN ACCEPTED BY NAD TO FORM NADH

2 - 2C ACETYL GROUP FORMED FROM OXIDISED PYRUVATE COMBINES WITH COENZYME A TO PRODUCE ACETYLCOENZYME A

3 - CO2 FORMED FROM EACH PYRUVATE

KREBS CYCLE

MATRIX OF MITOCHONDRIA

1 - 2C ACETYLCOENZYME A COMBINES WITH 4C MOLECULE TO GIVE 6C MOLECULE

2 - 6C MOLECULE LOSES CO2 AND HYDROGENS TO GIVE 4C MOLECULE AND SINGLE ATP DUE TO SUBSTRATE LEVEL PHOSPHORYLATION, PRODUCES NAH AND FADH

3 - 4C MOLECULE COMBINES WITH NEW ACETYLCOENZYME A TO RESTART CYCLE

YIELD PER PYRUVATE

- REDUCED COENZYMES: NADH, FADH, WHICH CAN PRODUCED ATP

- 1 X ATP

- 3 X CO2

AS 2 PYRUVATE COME FROM ONE GLUCOSE, YIELD FROM 1 X GLUCOSE DOUBLE THE QUANTITIES ABOVE.

COENZYMES - MOLECULES SOME ENZYMES REQUIRE TO FUNCTION

NAD - WORKS W/ HYDROGENASE ENZYMES THAT CATALYSE REMOVAL OF H+ AND TRANSFER THEM TO OTHER MOLECYLES SUCH AS H+ CARRIES IN OXIDATIVE PHOSPHORYLATION

IMPORTANCE OF KREBS CYCLE

BREAKS DOWN MACROMOLECULES INTO SMALLER ONES. PYRUVATE BROKEN INTO CO2
PRODUCES H ATOMS, CARRIED BY NAD TO ELECTRON TRANSPORT CHAIN FOR OXIDATIVE PHOSPHORYLATION - LEADS TO PRODUCTION OF ATP
REGENERATES 4C MOLECULES THAT COMBINES W/ ACETYLCOENZYME A WHICH WOULD OTHERWISE ACCUMULATE
SOURCE OF INTERMEDIATE COMPOUNDS USED BY CELLS IN MANUFACTURE OF OTHER SUBSTANCES LIKE FATTY ACIDS, AMINO ACIDS AND CHLOROPHYLL

ELECTRON TRANSPORT CHAIN

IN THE CRISTAE

HYDROGEN ATOMS PRODUCED DURING GLYCOLYSIS AND THE KREBS CYCLE COMBINE WITH NAD AND FAD IN THE CRISTAE
NADH DONATES ELECTRONS OF HYDROGEN TO FIRST ELECTRON CARRIER
FADH DONATES ELECTRONS OF HYDROGEN TO SECOND ELECTRON CARRIER, MISSES THE FIRST ATP PRODUCTION
PROTONS FROM HYDROGEN RELEASED
ELECTRONS PASS ALONG ELECTRON CARRIER CHAIN BY OXIDATION - REDUCTION REACTIONS
EACH OXIDATION REDUCTION REACTION RELEASES ENERGY, WHICH IS USED TO ACTIVELY TRANSPORT H+ ACROSS THE CRISTAE MEMBRANES INTO THE INTERMEMBRANAL SPACE
CHANNEL PROTEIN THAT H+ GOES THROUGH IS A PROTON PUMP
ACCUMULATION OF H+ IN THE INTERMEMBRANAL SPACE CREATES AN ELECTROCHEMICAL GRADIENT THAT THEY WOULD MOVE DOWN INTO THE INTERMEMBRANAL SPACE
H+ CAN ONLY DIFFUSE THROUGH THE MEMBRANE THROUGH ATPsynthase WHICH IS ACTIVATED WHEN H+ DIFFUSES THROUGH IT, DRIVES THE REACTION OF ADP + Pi --> ATP
AT THE END OF THE ELECTRON TRANSPORT CHAIN, PROTONS REASSOCIATE WITH ELECTRONS TO FORM HYDROGEN, AND ARE THEN PICKED UP BY O TO FORM H2O

Nächster

Vorher

Respiration