Due to the absence of air bladder, fishes belonging to the class Chondrichthyes have to swim constantly. How important is the presence of air bladder in these fishes?

How important is the presence of air bladder in Pisces?

In a fish swim bladder is an orgản for a: Digestion b. Buoyancy c. Respiration d. Food storage

You are provided with two fishes Catla (Bony fish) and Shark (Cartilagenous fish). Prepare a table showing difference in: a) Position of mouth b) Air bladder. c) Scales d) Fertilization

Which one of the following statement is not true? Oxides of sulphur, nitrogen and carbon are the most widespread air pollutant.,, pH' of drinking water should be between 5.5-9.5 ,, Concentration of DO below 6 ppm is good for the growth of fish,, Clean water would have a BOD value of less than 5 ppm