Question

Which of the following characteristics is incorrect with respect to cockroaches?

• A. Hypopharynx lies within the cavity enclosed by the mouthparts
• B. A ring of gastric caeca is present at the junction of the midgut and hindgut
• C. In females, the $7\mathrm{th}-9\mathrm{th}$sterna together form a genital pouch
• D. $10\mathrm{th}$ abdominal segment in both sexes bears a pair of anal cerci

Answer 1

The correct option is B

A ring of gastric caeca is present at the junction of the midgut and hindgut

The correct option is B.

Explanation for the correct answer:

1. At the confluence of the foregut and midgut is a ring of $6-8$ blind tubules called the hepatic or gastric caeca, which release digestive juice.
2. The glandular cells of the midgut's interior lining and the hepatic caeca create digestive enzyme-rich juice.

Explanation for the incorrect answer:

Option A

1. Malpighian tubules can be found at the confluence of the midgut and the hindgut.
2. A midline flexible lobe called the hypopharynx is located within the oral cavity, which is contained by the mouthparts (tongue).

Option

The $7\mathrm{th}$ sternum of female cockroaches is boat-shaped, and it creates a genital pouch with the 8th and 9th sterna.

Option D

The male cockroach's $10\mathrm{th}$ abdominal segment carries a pair of anal cerci, whereas the female cockroach's $9\mathrm{th}$ sternum bears a pair of chitinous anal styles.

Final Answer:

A ring of gastric caeca is present at the junction of the midgut and hindgut is incorrect with respect to cockroaches.