Q.1:- Differentiate between
(a) Respiration and Combustion
(b) Glycolysis and Krebs’cycle
(c) Aerobic respiration and Fermentation
Answer:-
(a) Respiration and Combustion
|
Respiration
|
Combustion
|
| It is a biochemical process. | It is a physiochemical process. |
| It occurs inside the cells. | It does not occur inside cells. |
| It is a biologically-controlled process. | It is an uncontrolled process. |
| No light is produced | Light may be produced |
| ATP is generated. | ATP is not generated. |
| Enzymes are required | Enzymes are not required |
OR
Respiration is a type of combustion. But while combustion is an uncontrolled process, respiration is controlled with high precision. Respiration takes place inside the cells of living beings, while combustion can take place anywhere.
(b) Glycolysis and Krebs’cycle
|
Glycolysis
|
Krebs’cycle
|
| The breakdown of glucose to pyruvic acid is called glycolysis. | The further processing of pyruvic acid through aerobic route is called Krebs’ cycle. |
| It is a linear pathway. | It is a cyclic pathway. |
| It occurs in the cell cytoplasm. | It occurs in the mitochondrial matrix. |
| It occurs in all living beings. | It occurs in aerobic respiration. |
| It generates 2 NADH2 and 2 ATP molecules on the breakdown of one glucose molecule. | It produces 6 NADH2, 2 FADH2, and 2 ATP molecules on the breakdown of two acetyl-CoA molecules. |
| No carbon dioxide evolved | Carbon dioxide evolved |
OR
Breakdown of glucose into pyruvic acid is called glycolysis, while further processing of pyruvic acid through aerobic route is called Krebs’ cycle. Glycolysis happens in all living beings, while Krebs’ cycle happens in aerobes only. Glycolysis happens in cytoplasm, while Krebs’ cycle happens in mitochondria.
(c) Aerobic respiration and Fermentation
|
Aerobic respiration
|
Fermentation
|
| The complete oxidation of organic substances in the presence of oxygen. | The incomplete oxidation of glucose in the absence of oxygen. |
| It occurs in the cytoplasm and mitochondria | It occurs in the cytoplasm |
| The end products are carbon dioxide and water | The end products are ethyl alcohol and carbon dioxide |
| Complete oxidation of the respiratory substrate takes place | Incomplete oxidation of the respiratory substrate takes place |
| About 36 ATP molecules are produced | Only 2 ATP molecules are produced |
OR
Anaerobic respiration is also called fermentation. Ethanol and lactic acid are the major products of fermentation.