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. **Understanding the Nervous System of Cockroach:**
- The cockroach has a nervous system that consists of both fused and segmented ganglia. These ganglia are connected along the ventral side of the body by longitudinal connectors.

2. **Identifying the Ganglia in Different Body Regions:**
- The cockroach's body is divided into three main regions: the head, thorax, and abdomen.
- In the thorax, there are **3 ganglia**.
- In the abdomen, there are **6 ganglia**.

3. **Calculating Total Ganglia:**
- To find the total number of ganglia, we need to add the ganglia from the thorax and abdomen:
- Total ganglia = Thoracic ganglia + Abdominal ganglia
- Total ganglia = 3 (thoracic) + 6 (abdominal) = **9 ganglia**.

4. **Understanding the Pairing of Ganglia:**
- The ganglia in the thorax are often referred to as 3 pairs (one for each segment), and the abdominal ganglia are referred to as 6 pairs (one for each segment).
- Therefore, we can express the total as 3 pairs (thoracic) + 6 pairs (abdominal).

5. **Final Answer:**
- The total number of ganglia in a cockroach is **9**, which can also be expressed as 3 pairs in the thorax and 6 pairs in the abdomen.