Respiration in ruhi fish is done in two stages. Inhalation or inhalation and exhalation or exhalation.
1. Respiration or Respiration: Ruhi fish takes in oxygen dissolved in water to carry out respiration. For unidirectional water flow, water enters through the stomata and exits through the gills. In this case the mouth and pharynx act as pumps. First, the mouth and pharynx expand and the stoma opens. Water enters the mouth and pharynx. The front of the gill chamber then expands and water enters the gill chamber. Then the pressure in the gill chamber decreases and water flows up the gills. Finally, the buccal and pharyngeal chambers are narrowed. At this time, the oral cavity is closed so that water cannot escape. Dr. Siddiq Publications
2. Inhalation or Exhalation: Contraction of the pharynx causes water to rise to the top of the gills. The gill lamella is flooded with water. Gaseous exchange occurs between blood and water in the lamellar capillary network. Oxygen from the water enters the blood and carbon dioxide from the blood enters the water. Oxygen enters the body through blood and carbon dioxide is released through water.