In an ovule,the seat of many biochemical reactions is

Options

A. integuments
B. nucellus
C. embryo sac
D. chalaza

Answer

To answer the question "In an ovule, the seat of many biochemical reactions is," we need to analyze the components of the ovule and their functions. Here’s the step-by-step solution:

### Step 1: Understand the Structure of the Ovule
The ovule is a crucial part of the female reproductive system in flowering plants, located within the ovary. It is responsible for developing into a seed upon fertilization.

**Hint:** Identify the main components of the ovule and their roles in reproduction.

### Step 2: Identify the Key Components
The ovule consists of several parts, including:
- **Integuments**: Protective layers surrounding the ovule.
- **Nucellus**: The tissue inside the ovule that contains the female gametes.
- **Embryo sac**: The structure that contains the egg cell and other cells involved in fertilization.
- **Chalaza**: The region where the integuments and nucellus are joined.

**Hint:** Focus on the functions of each part of the ovule to determine where biochemical reactions might occur.

### Step 3: Analyze the Role of the Chalaza
The chalaza is a significant part of the ovule. It serves as a junction where the integuments and the nucellus meet. Nutrients from the plant travel through the vascular tissue into the chalaza, which then distributes them to the nucellus.

**Hint:** Consider where nutrient transfer and biochemical processes are likely to take place within the ovule.

### Step 4: Consider Other Options
- **Integuments**: Primarily protective; not the main site for biochemical reactions.
- **Nucellus**: Contains the gametes but is not specifically known for many biochemical reactions.
- **Embryo sac**: While it plays a role in reproduction, it is not the primary site for biochemical reactions.

**Hint:** Eliminate options that do not align with the role of the chalaza in biochemical processes.

### Step 5: Conclusion
Based on the analysis, the chalaza is the part of the ovule that serves as the seat of many biochemical reactions, particularly due to its role in nutrient transfer and its position in the ovule structure.

**Final Answer:** The correct answer is **chalaza**.