Question

Liver is trilobed in
(a)Chondrichthyes
(b)Osteichthyes
(c)Both (a) & (b)
(d)Cyclostomes

Answer 1

Hint: The liver is an organ that dates exercise chemicals and metabolizes drugs. It filters the blood coming from the digestive tract before passing it to the rest of the body and secretes bile which helps in the digestion of fats and ends up back in the intestine. It produces certain proteins for the blood plasma.

Complete answer:
The liver is trilobed in Osteichthyes. Osteichthyes are Bony fishes that have skeletons primarily composed of bone tissue as the opposite of cartilage. Osteichthyes is the largest class of vertebrates and is divided into ray-finned fish which is also known as Actinopterygii and lobe-finned fish which is also known as sarcopterygian. The fossils of Bony fishes are known for about 420 million years. They consist of a pattern of cranial bones medial insertion of mandibular muscle in the lower jaw and the head is covered with large dermal bones. Bony fishes had simple lungs that help them to breathe in low oxygen water and this has evolved into swim bladders which helps them to create a neutral balance between sinking and floating.

Additional Information: Chondrichthyes: They show contains the cartilaginous fishes which are Jawed vertebrates with paired fins, scales, and a heart with its chamber in series and skeletons made up of cartilage rather than bone. During development, the notochord is replaced by the vertebral column gradually. In Holocephali, the notochord stays intact. The vertebral column is reduced in some deep water sharks. They do not contain bone marrow, red blood cells. They are produced in Leydig's organ which is found only in the cartilaginous fishes.
Cyclostomes: They jawless fishes with horny epidermal structures that function as teeth. It is included in the Agnatha which consists of several groups of extinct armored fishes known as ostracoderms. Some fossils are closely related to the vertebrates with jaws known as gnathostomes. They have evolved oxygen transport hemoglobins from the Jawed vertebrates.
So, the correct answer is ‘Osteichthyes’.

Note: The heaviest Bony fish in the world is the ocean sunfish and the longest Bony fish is a type of oarfish. The catfish has over 27000 taste words and the loudest fish is the croaker. Grass carp is the most common fish. The Tuna fish can swim at a speed of up to 70 kmph.