All enzymes are present in matrix of mitchondria for TCA cycle except:

Options

A. `alpha`-Ketoglutaric acid dehydrogenase
B. Citrate synthetase
C. Succinate dehydrogenase
D. Decarboxylase

Answer

To solve the question "All enzymes are present in the matrix of mitochondria for TCA cycle except:", we will follow these steps:

### Step 1: Understand the TCA Cycle
The TCA cycle, also known as the Krebs cycle, occurs in the mitochondrial matrix and involves a series of enzymatic reactions that break down pyruvic acid to produce energy.

**Hint:** Remember that the TCA cycle is a key metabolic pathway for energy production.

### Step 2: Identify the Enzymes Involved
Key enzymes involved in the TCA cycle include:
- Alpha-ketoglutarate dehydrogenase
- Citrate synthase
- Various decarboxylases

These enzymes are responsible for different reactions in the cycle and are all located in the mitochondrial matrix.

**Hint:** Focus on the specific roles of these enzymes in the TCA cycle.

### Step 3: Locate the Exception
Among the enzymes mentioned, succinate dehydrogenase is unique because it is located in the inner mitochondrial membrane rather than the matrix. This enzyme catalyzes the conversion of succinate to fumarate.

**Hint:** Look for the enzyme that does not fit the pattern of being located in the matrix.

### Step 4: Conclusion
Based on the information gathered, the answer to the question is that all enzymes of the TCA cycle are present in the mitochondrial matrix except for succinate dehydrogenase.

**Final Answer:** Succinate dehydrogenase is the enzyme that is not present in the matrix of mitochondria for the TCA cycle.

### Summary of Steps:
1. Understand the TCA cycle and its location.
2. Identify the enzymes involved in the TCA cycle.
3. Locate the exception among these enzymes.
4. Conclude with the correct answer.