Question

Which one of the following is the true description about an animal concerned?

• A. Rat- Left kidney is slightly higher in position than the right one.
• B. Cockroach- 10 pairs of spiracles (2 pairs on thorax and 8 pairs on abdomen).
• C. Earthworm- The alimentary canal consists of a sequence of pharynx, oesophagus, stomach gizzard and intestine.
• D. Frog- Body divisible into three regions- head, neck and truck.

Answer 1

The correct option is B Cockroach- 10 pairs of spiracles (2 pairs on thorax and 8 pairs on abdomen).

In rats, the right kidney is slightly higher than the left one due to presence of liver on the right side and so, statement A is incorrect.
The alimentary canal of the earthworm is a straight tube throughout the length of the body consisting of (in the sequence), mouth and buccal chamber, pharynx, oesophagus, gizzard, stomach, intestine and anus. So, option C is incorrect.

The body of a frog is divisible into head and trunk and so, statement D is incorrect.
Cockroaches possess ten pairs of spiracles, two thoracic and eight abdominal.
Therefore, the correct answer is option B.