Question

In the female cockroach the anterior wall, roof, and floor of the genital pouch are formed respectively by following the abdominal sterna of
(a) $7^{th}$, $8^{th}$, and $9^{th}$ segments
(b) $8^{th}$, $9^{th}$, and $9^{th}$ segments
(c) $9^{th}$, $8^{th}$, and $7^{th}$ segments
(d) $8^{th}$, $9^{th}$, and ${10}^{th}$ segments

Answer 1

Hint: The three-segment of the abdomen which together comprises the reproductive tract and all three connected with each other in form of sterane.

Complete answer:
In cockroach, the abdomen consists of 10 segments where the female abdomen is boat shape with the $7^{th}$ , $8^{th}$, and $9^{th}$ sterna together from the genital part or brood pouch, where the $7^{th}$ sternite form the floor of the genital pouch, and the $8^{th}$ and $9^{th}$ sternite form roof and anterior wall. The genital pouch where the vagina opens and accessory reproductive gland form. The formation of the egg takes place inside the genital pouch which exerts out after formation and lay outside till the formation of the zygote.

So, the correct answer is the $7^{th}$ , $8^{th}$ , and $9^{th}$ segments.

Additional information: The male and female cockroach differ morphologically and anatomically both, as there is 7 sterna in female cockroach but 8 in the male cockroach. The 10 segments of cockroach consist of anal cerci. Both males and females differ in the shape of the abdomen also as a male cockroach has a round shape and a female cockroach has a boat shape of the abdomen. The bottom of the male consists of a thick black band whereas the male has one dark band at the bottom with the light band on the top.

Note: The lower part of a female cockroach is pointed due to the large genital chamber with vestibulum, together it is called a genital pouch. On average females produce 14-16 eggs, after the formation of egg females lay eggs in shady areas which leads to the development of nymph. Because of the presence of pointed ends, the female cockroach looks larger than the male cockroach.