What are the reactions in the equation for cellular respiration?

Answer 1

Basic Equation: C6H12O6 + 6O2 --> 6CO2 + 6H2O

Word Equation: Glucose + 6Oxygen --> 6Carbon Dioxide + 6Water

However this question is too general there are many reactions in the respiration reaction, glycolysis is the 1st stage of respiration that occurs in the cytoplasm not the mitochondia. There are 9 main steps...

Step 1: Glucose + ATP --(Hexokinase)--> Glucose 6 Phosphate + ADP

Step 2: Glucose 6 Phosphate --(Phosphoglucose Isomerase)--> Fructose 6 Phosphate

Step 3: Fructose 6 Phosphate + ATP --(Phosphofructose Kinase)--> Fructose-1,6-bisphosphate + ADP

Step 4: Fructose-1,6-Bisphosphate --(Aldolase)--> 2Glyeraldehyde 3 Phosphate

Step 5: 2Glyceraldehyde 3 Phosphate + 2(PO4)3- + 2NAD --(Dehydrogenase)--> x2 1,3-Bisphosphoglycerate + 2NADH

Step 6: x2 1,3-Bisphosphoglycerate + 2ADP --(Phosphoglycerate Kinase)--> x2 3-Phosphoglycerate + 2ATP

Step 7: x2 3-Phosphoglycerate --(Phosphoglycerate Mutase)--> x2 2-Phosphoglycerate

Step 8: x2 2-Phosphoglycerate --(Enolase)--> x2 Phosphoenolpyruvate

Step 9: x2 Phosphoenolpyruvate + 2ADP --(Pyruvate Kinase)--> 2Pyruvate + 2ATP * I realsise most of these rections could be divided through by 2 but you've got to realise that for 1 glucose in glycolysis there is a net gain of 2 ATP's and 2 NAD's are reduced.

The next stage of respiration is much more simple and occurs in the matrix of the mitochondria, The Link Reaction, there are 2 main steps...

Step 1: Pyruvate + NAD --(Decarboxylase & Dehydrogenase)--> Acetyl + CO2 + NADH

Step 2: Acetyl + Co-Enzyme A --> Acetyl CoA

The Next stage of respiration is the citric acid cycle also known as the krebs cycle, it agin occurs in the matrix of the mitochondria and there are 8 main steps...

Step 1: Acetyl CoA + Oxoloacetate --(Citrate Synthase)--> Citrate + CoA

Step 2: Citrate --(Aconitase)--> Isocitrate

Step 3: IsoCitrate + NAD --(Decarboxylase & Dehydrogenase)--> Alpha Ketoglutarate + CO2 + NADH

Step 4: Alpha Ketoglutarate + NAD + CoA --(Decarboxylase & Dehydrogenase)--> Succinyl CoA + NADH + CO2

Step 5: Succinyl CoA +ADP +(PO4)3- --(Succinyl CoA Synthetase)--> ATP + Succinate

Step 6: Succinate + FAD --(Dehydrogenase)--> Fumarate + FADH

Step 7: Fumarate --(Fumarase)--> Malate

Step 8: Malate + NAD --(Dehydrogenase)--> Oxaloacetate + NADH

And the cycle starts again

The Final stage of photosynthesis is the electron transport chain, there are no equations in this step it consists of 2 processes chemiosmosis and oxadative Phosphorylation. It is where the reduced NAD & FAD Come to be reoxidised.

http://hopes.stanford.edu/sites/hopes/files/f_j13electtrans.jpg

Sometimes NAD/FAD are reduced to N/FADH2 depending on the H+ concentration.

The electron transport chain is a system of proteins called cytochromes in the inner mitochondrial membrane that contain a Haem group with an iron atom in the middle.

NADH--> NAD + H

H --> H+ + e-

The NADH is oxidised at complex 1 & FADH at complex 2 which is ialso the succinate dehydrogenase enzyme. The electons are then passed along the cytochromes oxidising and reducing the iron atoms.

Fe3+ + e- --> Fe2+

Fe2+ --> Fe3+ +e-

This in turn creates energy this energy is used to actively transport the H+ ions from the matrix into the inter membrane space across specific prteins this is chemiosmosis. A H+ ion concentration gradient and hence potential energy builds up.

The hydrogen ions begin to flow back the the ATP synthase enzymes driving the rotation of part of the enzyme...

ADP + (PO4)3- --> ATP This is oxidative phosphorylation.

Here is where the oxygen is finally used. It is the final elecrton acceptor and is reduced to oxide, the H+ ions join to the H+ ions to form water,

4e- + 4H+ + O2 --> 2H2O

End of respiration

You should realise though that these are only the main reactions, sometimes GTP/CTP/TTP are used in place of ATP, water is needed in some reactions to catalyse the hydrolysis of some molecules, so this isn't the whole picture.

Answer 2

The equation for cellular respiration is

6O2+C6H12O6 +> 6CO2 + 6H2O + ATP

Hence the reactants are oxygen and glucose, while the products are carbon dioxide, water and ATP.