overview of cellular respiration.....

3. • Glycolysis:
– Cytosol
• Oxidation of Pyruvate:
– Mitochondrial Matrix
• The Krebs Cycled:
– Mitochondrial Matrix
• Electron Transport Chain and
Cheimiosmotic
Phosphorylation:
– Mitochondrial Cristae

5. • Glyco-glucose,lysis-
breakdown
• Involves member of
enzyme-Controlled
reaction
• It takes place –cytoplasm
of cell
• It does not require oxygen
• Common for both aerobic
and anaerobic reaction

6. • Glucose phosphorylated by ATP to glucose 6 phosphate
• Phosphorylated glucose – no longer recognized – glucose
transport system , therefore – trapped inside the cell
• Enzyme involved is kinase
• Glucose 6 phosphate-isomerised-fructose 6 phosphate
• Enzyme involved is isomerize
• Fructose 6 phosphate-phosphorylated by ATP to fructose
1,6phosphate
• Enzyme involved is kinase
• Fructose 1,6 phosphate splits to glycerate 3 phosphate
• Glycerate 3 phosphate converts to pyruvate
• Glycerate 3 phosphate when converted to pyruvate it forms 2
NADH2 and ATP

7. • 2 molecules of ATP( 4 molecules are produced
but 2ATP are used up)
• 2 molecules of NADH
• 2 molecule of pyruvate
• Now this Pyruvate will form Acetyl Co-A

8. • Pyruvate- Matrix of mitochondria from cytoplasm
• Pyruvate- Decarboxylated (Removal of carbon in
form of carbon dioxide)
• Piruvate- Dehydrogenated (Removal of hydrogen)
• Hydrogen is transferred to hydrogen acceptor
NAD+ to NADH+ H+
• Pyruvate- Acetate
• Acetate combines with coenzyme A to form acetyl
coenzyme

10. • 2 molecules of NADH
• 2 molecule of Acetyl Co-A
• Now Acetyl Co-A will enter into TCA/ Kreb
cycle

11. • Discovered by sir Hans
Kerbs-1937
• Citric acid cycle /
Tricarboxylic acid cycle
(TCA)
• Occurs- In Matrix of
mitochondria
• Occurs only in aerobic
reaction

13. • Acetyl co enzyme A (2C) + oxaloacetate(4C) –citrate
• Reaction is called condensation
• Enzyme involved citrate synthetase
• Citrate isomerizes to isocitrate(6C)
• Isocitrate undergo Oxidative decarboxylation to give α-ketogluterate(5C)
• Carbon dioxide is produced
• NAD+, hydrogen acceptors and NADH is formed
• Enzyme involved is isocitrate dehydrogenase
• X –ketogluterate(5C) undergo oxidative decarboxylation & dehydrogenation
gives succinyl CoA(4C)
• CO2 is produced & NADH is formed.
• Enzyme used is α- ketogluterate dehydrogenase.
• Succinyl CoA(4C) gives succinate (4C)
• ATP is formed from ADP+pi
• Enzyme used is succinyl CoA Synthetase
• Succinate undergoes dehydrogenation and gives Fumerate(4C)
• FAD (Flavine adenine dinucleotide) gives hydrogen acceptor and form FADH2
• Enzyme used is succinate dehydrogenase
• Fumerate undergoes hydrogenation and gives maltate(4C)
• Enzyme used is fumerate
• Maltate undergo dehydrogenation and gives oxaloacete (4C)
• (NAD+)+(H+) gives NADH
• Enzyme used is malate dehydrogenase.

14. • 3 molecules of NADH
• 1 molecule of FADH2
• 1 molecule of ATP
• So total:
• 6 molecules of NADH
• 2 molecule of FADH2
• 2 molecule of ATP
From 1 molecule of
Acetyl Co-A
From 2 molecule of
Acetyl Co-A

15. • Now these NADH & FADH2 will enter into ETC
and will give ATP

16. • Oxygen is required during the
final stage of reaction.
• Oxydative phosphorylation is a
process by which ATP is formed
as electron are transferred from
NADH & FADH2 to oxygen via
series of electron carrier.
• Location- inner membrane of the
mitochondria.
• E.T.C involves Chain of electron
carrier molecules.
• Electron from NADH & FADH2
are transferred to Oxygen

17. • Hydrogen atom splits to hydrogen ions(H+)
and electrons.
• Transfer of electrons along the chain releases
sufficient energy to make ATP
• Hydrogen is passed on to oxygen to form
water.

20. • NADH & FADH2 – formed during – glycolysis & Krebs cycle are
passed to ETC
• ETC – present – inner membrane space and consists of
cytochromes
• NADH & FADH2 – oxidized – hydrogen are released
• Hydrogen now splits into electrons & protons
• Electrons – pass along – electron carrier and transferred to oxygen
• Protons H+ are actively pumped from – matrix to the outer
compartment i.e. intermembrane space
• A proton gradient – created b/w the outer compartment and the inner
matrix
• Protons cannot diffuse through cristae membrane
• Protons flow only down the gradient – matrix through ATP synthase
channels this is known as chemiosmosis
• Protons flow – ATP synthase channel (F1 channels) they generate
energy to phosphorylate ADP into ATP in the presence of enzyme
ATP Synthase
• Later proton combines with oxygen
• 2e- + 2H+ + ½ O2 = H2O