Answer
Verified
455.1k+ views
Hint: Decarboxylation is the process of removal of the carboxyl group from a compound with the release of a carbon dioxide molecule. So, the number of steps in which a ${C}{O}_{2}$ molecule is released after removal of a carboxyl from a compound is the number of decarboxylation reactions in one Krebs’ cycle.
Complete answer:
Krebs’ cycle is the central pathway for the metabolism of carbohydrates, fats, and proteins. It begins with a citric acid molecule which is a 6- carbon compound and ends at Oxaloacetate which is a 4-carbon compound which indicates the removal of two carboxyl groups.
These carboxyl groups are removed with the release of a ${C}{O}_{2}$ molecule in two different steps.
- The first oxidative decarboxylation takes place at the fourth step of the TCA cycle where isocitrate is converted to 5-carbon α-ketoglutarate, with the release of a pair of hydrogen atoms and a molecule of carbon dioxide.
- The second oxidative decarboxylation occurs at the fifth step of the Krebs’ cycle where a molecule of coenzyme-A reacts with the α-ketoglutarate to form a 4-carbon compound succinyl- coenzyme A and releasing carbon dioxide and a pair of hydrogen atoms.
So, the answer is, “Two”.
Note:Decarboxylation is the reaction in which a carboxyl group is removed and it generally refers to the reactions of carboxylic acids. The reverse of this process in which there is an addition of a ${C}{O}_{2}$ molecule to a compound is called carboxylation and it is the first chemical step in photosynthesis.
Complete answer:
Krebs’ cycle is the central pathway for the metabolism of carbohydrates, fats, and proteins. It begins with a citric acid molecule which is a 6- carbon compound and ends at Oxaloacetate which is a 4-carbon compound which indicates the removal of two carboxyl groups.
These carboxyl groups are removed with the release of a ${C}{O}_{2}$ molecule in two different steps.
- The first oxidative decarboxylation takes place at the fourth step of the TCA cycle where isocitrate is converted to 5-carbon α-ketoglutarate, with the release of a pair of hydrogen atoms and a molecule of carbon dioxide.
- The second oxidative decarboxylation occurs at the fifth step of the Krebs’ cycle where a molecule of coenzyme-A reacts with the α-ketoglutarate to form a 4-carbon compound succinyl- coenzyme A and releasing carbon dioxide and a pair of hydrogen atoms.
So, the answer is, “Two”.
Note:Decarboxylation is the reaction in which a carboxyl group is removed and it generally refers to the reactions of carboxylic acids. The reverse of this process in which there is an addition of a ${C}{O}_{2}$ molecule to a compound is called carboxylation and it is the first chemical step in photosynthesis.
Recently Updated Pages
what is the correct chronological order of the following class 10 social science CBSE
Which of the following was not the actual cause for class 10 social science CBSE
Which of the following statements is not correct A class 10 social science CBSE
Which of the following leaders was not present in the class 10 social science CBSE
Garampani Sanctuary is located at A Diphu Assam B Gangtok class 10 social science CBSE
Which one of the following places is not covered by class 10 social science CBSE
Trending doubts
Which are the Top 10 Largest Countries of the World?
How do you graph the function fx 4x class 9 maths CBSE
Fill the blanks with the suitable prepositions 1 The class 9 english CBSE
The only snake that builds a nest is a Krait b King class 11 biology CBSE
The Equation xxx + 2 is Satisfied when x is Equal to Class 10 Maths
In Indian rupees 1 trillion is equal to how many c class 8 maths CBSE
Give 10 examples for herbs , shrubs , climbers , creepers
Why is there a time difference of about 5 hours between class 10 social science CBSE
Which places in India experience sunrise first and class 9 social science CBSE