In female cockroach 7th segment (sternum) is :

Options

A. Annular
B. Boat shaped
C. Filamentous
D. Spiral

Answer

To answer the question about the shape of the 7th segment (sternum) in female cockroaches, follow these steps:

### Step-by-Step Solution:

1. **Understand the Anatomy of Cockroaches**:
- Cockroaches have a segmented body structure. The abdomen consists of 10 segments in both male and female cockroaches.

2. **Identify the Specific Segment**:
- The question specifically asks about the 7th segment (sternum) in female cockroaches.

3. **Examine the Options Provided**:
- The options given are:
- a) Annular
- b) Boat shape
- c) Filamentous
- d) Spiral

4. **Analyze the Correct Shape**:
- In female cockroaches, the 7th sternum is known to be boat-shaped. This is a distinctive feature that helps in identifying female cockroaches.

5. **Consider the Functionality**:
- The 7th sternum, along with the 8th and 9th segments, forms a brood or genital pouch, which is crucial for reproduction.

6. **Conclude the Correct Answer**:
- Based on the anatomical structure and the options provided, the correct answer is that the 7th segment (sternum) in female cockroaches is boat-shaped.

### Final Answer:
The shape of the 7th segment (sternum) in female cockroaches is **boat-shaped** (Option 2).

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