Co- factor and prosthetic groups are ………... compounds, …………... bound to apoenzyme.

Options

A. organic, transiently
B. inorganic, tightly
C. organic, tightly
D. inorganic, transiently

Answer

To solve the question regarding the nature of cofactors and prosthetic groups in relation to apoenzymes, let's break it down step by step.

### Step-by-Step Solution:

1. **Understanding Cofactors**:
- Cofactors are non-protein chemical compounds that assist enzymes in catalyzing reactions. They can be either inorganic ions (like metal ions) or organic molecules.

**Hint**: Remember that cofactors are essential for enzyme activity and can be either inorganic or organic.

2. **Understanding Prosthetic Groups**:
- Prosthetic groups are a specific type of cofactor that are tightly or covalently bound to the enzyme (apoenzyme). They are usually organic molecules and play a crucial role in the enzyme's function.

**Hint**: Prosthetic groups are a subset of cofactors that are permanently attached to the enzyme.

3. **Defining Apoenzyme**:
- An apoenzyme is the protein part of an enzyme, which requires a cofactor or prosthetic group to become active. When the apoenzyme binds with a cofactor, it forms a holoenzyme.

**Hint**: The apoenzyme is inactive until it binds with a cofactor or prosthetic group.

4. **Analyzing the Options**:
- The question provides options:
- Organic transiently bound
- Inorganic tightly bound
- Organic tightly bound
- Inorganic transiently bound
- Based on our understanding, we know that both cofactors and prosthetic groups are organic compounds that are tightly bound to the apoenzyme.

**Hint**: Focus on the binding nature of cofactors and prosthetic groups to determine the correct option.

5. **Final Answer**:
- Therefore, the correct completion of the statement is: "Cofactor and prosthetic groups are **organic compounds**, **tightly** bound to apoenzyme."

### Summary:
Cofactors and prosthetic groups are essential for enzyme function, being organic compounds that are tightly bound to apoenzymes, making them crucial for the catalytic activity of enzymes.