NEET BIOLOGY

Detailed explanation-1: -Land animals, such as lions, have lungs to take in oxygen from the air. Fishes, on the other hand, cannot breathe in oxygen directly from the atmosphere. So they have specialised organs called gills to help them breathe in the oxygen dissolved in water. Q.

Detailed explanation-2: -Oxygen and carbon dioxide dissolve in water, and most fishes exchange dissolved oxygen and carbon dioxide in water by means of the gills.

Detailed explanation-3: -Gills contain many filaments, each with thousands of tiny folds called lamellae, which greatly increase the surface area that comes into contact with water. Dissolved oxygen in seawater passes through thin membranes in the lamellae and enters the fish’s blood, and carbon dioxide is eliminated.

Detailed explanation-4: -A gill (/ɡɪl/ ( listen)) is a respiratory organ that many aquatic organisms use to extract dissolved oxygen from water and to excrete carbon dioxide. The gills of some species, such as hermit crabs, have adapted to allow respiration on land provided they are kept moist.

Detailed explanation-5: -A fish’s gills absorb oxygen from the water. Carbon dioxide passes out into the water through the gills as waste. The water then flows out of the gills.