Question

ASSERTION : Lateral line system is found in fishes and aquatic larval amphibians.
REASON : Lateral line system has receptors which are the clusters of sensory cells derived from ectoderm
A) Both Assertion and Reason are correct and Reason is the correct explanation for Assertion
B) Both Assertion and Reason are correct and Reason is not the correct explanation for Assertion
C) Assertion is correct but Reason is incorrect.
D) Both Assertion and Reason are incorrect

Answer 1

Hint:A unique sense organ is present in amphibians and fishes which help in detecting movement and change in pressure in the water surrounding them. It is present in all aquatic vertebrates.

Complete answer:
To answer this question, we must know about the lateral line and its function.
The special and unique tactile sense organ present in fishes and amphibians is called the lateral line. Lateral line is made up of mechanoreceptors called the neuromast which is present in an interconnected series from head to body. They appear on the surface of the skin.

The neuromast cells are made up of sensory cells which are embedded in jelly like sheath called the cupula. Each sensory cell has tiny cilia which are stimulated by the movement of water. The lateral line helps the aquatic animals to sense the direction of water movement. This helps the fishes to sense the nearby predators or prey.

Thus the correct answer is option (B).

Note:All the fishes have lateral lines. It is more developed in some than in others. It is visible as faint lines which run along the length down each side from the vicinity of the gill covers till the tail.