Read the following statements with respect to cartilaginous fishes: a. In males pectoral fins bear clasper. b. Heart have two chambered with one atrium and one ventricle. c. Mouth is terminal in which teeth are modified placoid scales are backwardly directed. d. Due to absence of swim/air bladder, they have to swim constantly to avoid sinking. Correct options from above are
The correct option is 4: b and d only The correct option is 4, which includes statements b and d. Cartilaginous fishes, belonging to the class Chondrichthyes (sharks, rays, and chimaeras), are fundamentally characterized by their skeleton composed entirely of cartilage, distinguishing them from the bony fishes (Osteichthyes). Statement b correctly describes their circulatory system, which is common to all fish. The heart is a two-chambered structure, consisting of one…Read More
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