The number of spiracles in Periplaneta americana is

Options

A. 10
B. 20
C. 8
D. 6

Answer

To determine the number of spiracles in Periplaneta americana (the scientific name for the cockroach), we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Organism**: Recognize that Periplaneta americana refers to the common cockroach.

2. **Understand Spiracles**: Spiracles are small openings on the body of insects that facilitate respiration. They are also known as stigmata.

3. **Count the Pairs of Spiracles**: It is known that cockroaches have 10 pairs of spiracles. This means there are 10 pairs located on the body.

4. **Calculate the Total Number of Spiracles**: Since each pair consists of 2 spiracles, we multiply the number of pairs by 2:
\[ \text{Total Spiracles} = \text{Number of Pairs} \times 2 = 10 \times 2 = 20 \]

5. **Conclusion**: Therefore, the total number of spiracles in Periplaneta americana is 20.

### Final Answer:
The number of spiracles in Periplaneta americana is **20**.

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