Number of thoracic and abdominal ganglia in cockroach respectively is

Options

A. six, three
B. six, six
C. three , six
D. three, three

Answer

To solve the question regarding the number of thoracic and abdominal ganglia in a cockroach, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Structure of the Cockroach Nervous System**:
- The cockroach has a segmented nervous system that consists of a series of ganglia.

2. **Identify the Types of Ganglia**:
- The ganglia are divided into two main regions: thoracic and abdominal ganglia.

3. **Count the Thoracic Ganglia**:
- In cockroaches, there are **3 thoracic ganglia**. These are associated with the thoracic segments of the body.

4. **Count the Abdominal Ganglia**:
- There are **6 abdominal ganglia** in cockroaches, which correspond to the abdominal segments.

5. **Combine the Counts**:
- Therefore, the total number of thoracic and abdominal ganglia in a cockroach is 3 (thoracic) and 6 (abdominal).

6. **Select the Correct Option**:
- Based on the counts, the answer to the question is **3 thoracic ganglia and 6 abdominal ganglia**, which corresponds to option C (3 and 6).

### Final Answer:
The number of thoracic and abdominal ganglia in a cockroach respectively is **3 and 6**.

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