Question

Which of the following statements is correct about cockroach?

• A. In females, the $6^{\text{th }}$ sternum is boat-shaped and together with the $7^{\text{th }}$ and $8^{\text{th }}$ sterna form a brood or genital pouch
• B. In males, the genital pouch is bounded dorsally by $9^{\text{th }}$ and $10^{\text{th }}$ sterna and ventrally by the $9^{\text{th }}$ tergum
• C. Females bear a pair of short, threadlike anal styles which are absent in males
• D. The $10^{\text{th }}$ segment has a pair of filamentous structures called anal cerci

Answer 1

Answer: (D)

In cockroach, both males and females have 10 abdominal segments. In females, the genital pouch is made up of $7^{\text{th }}$, $8^{\text{th }}$ and $9^{\text{th }}$ abdominal sterna. Out of this, $7^{\text{th }}$ sternum is boatshaped. In male cockroaches, the genital pouch is bound by the $9^{\text{th }}$ abdominal sternum on the ventral side and $9^{\text{th }}$ and $10^{\text{th }}$ terga on the dorsal side. Anal styles are a pair of short structures found only in males. They are absent in females. Anal cerci are a pair of filamentous structures found in the $10^{\text{th }}$ abdominal segment of both males and females.