Question

Lateral line system is not well developed in
A. Shark
B. Catla
C. Seahorse
D. Frog

Answer 1

Hint: The lateral line system is a sensory system found in the fishes which serves to detect the movement and pressure changes in the surrounding water.

Complete answer:
 In frogs there is absence of lateral line. But in the larval stage of frogs (tadpoles) they have lateral lines present in their body. As they metamorphose into young frogs they lose their lateral line. We can say that the lateral line system is not well developed in the frogs.

Additional Information: The lateral line is present in the shark just under the skin on the snout and along either side of the body. The lateral lines are canals that are filled with fluid. Tiny hair like cells line their walls and are useful in detection of vibrations and sensation as low as 24hz. These lines also detect the odor plumes. They assist sharks to detect prey and potential mates. If these lateral lines get damaged then they lose the ability to smell even when their nostrils are in good condition.
-The lateral line is also present in Catla. Modified epithelial cells known as hair cells respond to the surrounding. These changes are then turned into the electrical impulses which then go to the central nervous system.
-Seahorses don't have any lateral lines present on them. They are bony fishes. They don’t have scales on their body when compared to other bony fishes. Their body is composed of bony plates and are arranged in series like rings.
So, the correct answer is ‘frog’.

Note: In some species the receptive organs of the lateral lines have been modified to function as an electroreceptor which are used to detect the electrical impulses. Lateral lines are used for schooling, preying and orientation.