Question

Sensory receptors in lateral line system of fishes are

• A. Cyanocytes
• B. Neuromasts
• C. Chloride cells
• D. Statocysts

Hint:

Neuromast = Mechanoreceptor of fish lateral line (detects vibrations and currents).
Chloride cells = Gill osmoregulatory cells.
This distinction is extremely common in fish biology exams.

Answer 1

The Correct Option is B

Step 1: Understanding the Concept:
Fishes possess specialized sensory systems to detect water currents, vibrations, and pressure changes in their aquatic environment.
The primary mechanoreceptive organ system responsible for this is the lateral line system.

Step 2: Detailed Explanation:
Let us review the functions of the cells listed:
Cyanocytes are hemolymph cells in some invertebrates, and are not sensory receptors in fishes.
Chloride cells (ionocytes) are specialized epithelial cells located in the gills of fishes, responsible for ion excretion and osmoregulation.
Statocysts are balance sensory organs found primarily in invertebrates.
The lateral line system of fishes consists of a series of fluid-filled canals running along the sides of the body and head.
The functional sensory units of this system are the neuromasts.
A neuromast is a group of hair cells covered by a gelatinous cupula.
When water movements or pressure waves bend the cupula, it deforms the cilia of the hair cells, generating nerve impulses.
These signals are sent to the brain, allowing the fish to detect water currents, orient itself, avoid obstacles, and locate prey or predators.
Therefore, neuromasts are the sensory receptors of the lateral line system.

Step 3: Final Answer:
The sensory receptors in the lateral line system of fishes are Neuromasts.