The total number of ganglia in cockroach are

Options

A. Three pairs thoracic and three abdominal
B. Three pairs thoracic and six pairs abdominal
C. Three pairs thoracic and eight pairs abdominal
D. Two pairs thoracic and six pairs abdominal

Answer

To determine the total number of ganglia in a cockroach, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Structure of the Cockroach**:
- The cockroach is divided into three main body segments: the head, thorax, and abdomen.

2. **Identify the Ganglia in Each Segment**:
- In the thorax, there are **3 pairs of ganglia**.
- In the abdomen, there are **6 pairs of ganglia**.
- The head has ganglia as well, but they are not counted separately since they are part of the thoracic ganglia.

3. **Calculate the Total Number of Ganglia**:
- Total pairs of ganglia = Pairs in thorax + Pairs in abdomen
- Total pairs of ganglia = 3 (thorax) + 6 (abdomen) = **9 pairs of ganglia**.

4. **Convert Pairs to Total Ganglia**:
- Since each pair consists of 2 ganglia, we multiply the number of pairs by 2.
- Total ganglia = 9 pairs × 2 = **18 ganglia**.

### Final Answer:
The total number of ganglia in a cockroach is **18**.

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