Question

Dog fish can be classified as ______ type of fish.
A. Cartilaginous
B. semi cartilaginous
C. Bony
D. Semi bony

Answer 1

Hint: The prickly dogfish is dim, with white spots, and is around 60 to 120 cm (2 to 4 feet) in length. Regularly found in thick schools, it goes after fishes and different spineless creatures. It is regularly an aggravation, as it takes goads and harms fishing nets, yet it is consumable and furthermore yields liver oil and is ground for compost. Its dorsal balance spines are related with little toxin organs and can cause difficult injuries.

Complete answer:
Chondrichthyes is a class that contains the cartilaginous fishes: they are jawed vertebrates with combined blades, matched nares, scales, a heart with its chambers in arrangement, and skeletons made of ligament instead of bone.The skeleton is cartilaginous. The notochord is steadily supplanted by a vertebral segment during improvement, aside from in Holocephali, where the notochord remains unblemished. In some deep water sharks, the section is diminished.
As they don't have bone marrow, red platelets are created in the spleen and the epigonal organ (extraordinary tissue around the balls, which is likewise thought to assume a part in the resistant framework). They are additionally delivered in the Leydig's organ, which is just found in certain cartilaginous fishes. The subclass Holocephali, which is an extremely specific gathering, needs both the Leydig's and epigonal organs.
The spiny dogfishes of the family Squalidae have a sharp spine before every one of their two dorsal blades. The most generally realized species is Squalus acanthias, called the barbed dogfish, spurdog, or skittle canine. It is bountiful along northern Atlantic and Pacific drifts; a firmly related, if not indistinguishable, structure possesses the southern portion of the world.
All chondrichthyans inhale through five to seven sets of gills, contingent upon the species. When all is said in done, pelagic species must continue swimming to keep oxygenated water traveling through their gills, while demersal species can effectively siphon water in through their spiracles and out through their gills. Notwithstanding, this is just an overall standard and numerous species contrast.

Hence, the correct answer is (A).

Note:
Their sound recognizing contraption has restricted reach and is regularly more remarkable at lower frequencies. A few animal types have electric organs which can be utilized for safeguard and predation. They have moderately basic minds with the forebrain not extraordinarily broadened. The structure and arrangement of myelin in their sensory systems are almost indistinguishable from that of tetrapods, which has driven transformative researchers to accept that Chondrichthyes were a foundation bunch in the transformative course of events of myelin improvement.