Question

Angler fish is a ___ fish.
(a) Cartilaginous
(b) Bony
(c) Semi-bony
(d) Semi-cartilaginous

Answer 1

Its body is made up of various bones along with teeth that are found on the upper jaw. Their body consists of an air-filled sac called the swim bladder in the gullet that helps them in maintaining buoyancy during floating.

Complete answer:
Bony fishes or Osteichthyes are aquatic vertebrates who possess a bony endoskeleton in the adult form. In the embryonic stage, the cartilaginous endoskeleton is found. They are cold-blooded in nature, thus called ectothermic, having more than 25,000 species. Bony fishes occur in various types of waters that include marine, freshwater, and brackish. Angler fish is an example of marine bony fish.
-The blood and tissue fluids of marine bony fishes are hypotonic to the surrounding medium. This results in the process of water loss through the process of osmosis from the body of the fishes into the environment. In these conditions, the marine bony fishes undergo various adaptations that include the absorption of large amounts of water into the gut which in turn will reduce the urine production. While the excess salt that has been absorbed by the body is excreted outside from the gills and the kidneys.
-Fishes like Labeo, Catla, Cirrhina are the freshwater bony fishes, the water flows inside the body continuously through the process of osmosis and the blood and tissue fluids are present in the lower amount thus creating the hypertonic medium to the surrounding. To balance this, kidneys excrete hypotonic urine i.e excess water is secreted out from the body into the environment.

So, the correct answer is ‘Bony.’

Note:
Bony fishes are ammonotelic i.e they secrete ammonia as the main excretory product. Nitrogenous waste that is produced during protein or nucleic acid metabolism includes substances such as ammonia, urea, and uric acid. The most toxic nitrogenous waste is the ammonia and then comes the urea and lastly the uric acid. For ammonia to be excreted out a large amount of water is required in the body and thus in most aquatic animals, it is the main excretory product.