(a) Respiration and combustion
|
Respiration |
Combustion |
|
1. |
It is a biochemical process. |
1. |
It is a physiochemical process. |
|
2. |
It occurs in the living cells. |
2. |
It does not occur in the living cells. |
|
3. |
ATP is generated |
3. |
ATP is not generated |
|
4. |
Enzymes are required |
4. |
Enzymes are not required |
|
5. |
It is a biologically-controlled process. |
5. |
It is an uncontrolled process. |
(b) Glycolysis and Krebs cycle
|
Glycolysis |
Krebs cycle |
|
1. |
It is a linear pathway. |
1. |
It is a cyclic pathway. |
|
2. |
It occurs in the cell cytoplasm. |
2. |
It occurs in the mitochondrial matrix. |
|
3. |
It occurs in both aerobic and anaerobic respiration. |
3. |
It occurs in aerobic respiration. |
|
4. |
It generates 2 NADH2 and 2 ATP molecules on the breakdown of one glucose molecule. |
4. |
It produces 6 NADH2, 2FADH2, and 2 ATP molecules on the breakdown of two acetyl-CoA molecules. |
(c) Aerobic respiration and fermentation
|
Aerobic respiration |
Fermentation |
|
1. |
Oxygen is used for deriving energy |
1. |
Occurs in the absence of oxygen |
|
2. |
Occurs in the cytoplasm and
mitochondria |
2. |
Occurs in the cytoplasm |
|
3. |
End products are carbon dioxide and water |
3. |
End products are ethyl alcohol and carbon dioxide |
|
4. |
Complete oxidation of the
respiratory substrate takes place |
4. |
Incomplete oxidation of the
respiratory substrate takes place |
|
5. |
About 36 ATP molecules are
produced |
5. |
Only 2 ATP molecules are produced |
