Prosthetic group is present in

Options

A. Complex proteins
B. Conjugated proteins
C. Secondary proteins
D. Essential proteins

Answer

To solve the question "Prosthetic group is present in," we need to understand what a prosthetic group is and its relation to proteins. Here’s a step-by-step breakdown:

### Step 1: Define Prosthetic Group
A prosthetic group is a non-amino acid component that is tightly and often covalently bonded to a protein. It is essential for the biological activity of the protein.

**Hint:** Remember that prosthetic groups are not part of the amino acid structure of proteins.

### Step 2: Identify Types of Proteins
Proteins can be classified into two main categories:
- **Apoproteins:** These are proteins without their prosthetic groups.
- **Holoproteins:** These are proteins that include their prosthetic groups.

**Hint:** Think about how the presence or absence of a prosthetic group changes the classification of a protein.

### Step 3: Understand Conjugated Proteins
Conjugated proteins are those that contain a prosthetic group. They are also known as heteroproteins because they consist of both protein and non-protein components.

**Hint:** Conjugated proteins are the ones that have additional components beyond just amino acids.

### Step 4: Analyze the Options
Now, let’s evaluate the options given in the question:
1. **Complex Protein:** This term is not specific and does not necessarily refer to proteins with prosthetic groups.
2. **Conjugated Protein:** This is the correct answer as it specifically refers to proteins that contain prosthetic groups.
3. **Secondary Protein:** This term refers to the structural level of proteins and does not relate to the presence of prosthetic groups.
4. **Essential Protein:** This term typically refers to proteins that must be obtained from the diet and does not imply the presence of prosthetic groups.

**Hint:** Focus on the definitions of the terms provided in the options.

### Step 5: Conclusion
Based on the definitions and classifications, the correct answer is that prosthetic groups are present in **conjugated proteins**.

**Final Answer:** Conjugated protein (Option 2).