Question

The spiracles found in cockroach are:

• A. Two pair in thorax and hundred pairs in abdomen
• B. Two pair in thorax and six pair in abdomen
• C. Two pair in thorax and eight pair in abdomen
• D. Two pair in thorax and four pair in abdomen

Answer 1

The correct option is C Two pair in thorax and eight pair in abdomen

Spiracles are the external openings containing tubules through which atmospheric air enters and escape out during gaseous exchange in cockroach and other insects. There are 20 spiracles, out of these two pairs are found in thoracic portion and rest 8 pairs are located in the abdomen region. Thoracic stigmata are somehow larger than abdominal spiracles.

So, the correct answer is 'Two pair in thorax and eight pair in abdomen'