NEET BIOLOGY

Detailed explanation-1: -The fishes breathe through the gills. The lungs are absent in fishes.

Detailed explanation-2: -Like us, fish also need to take in oxygen and expel carbon dioxide in order to survive. But instead of lungs, they use gills. Gills are branching organs located on the side of fish heads that have many, many small blood vessels called capillaries.

Detailed explanation-3: -Unlike land animals, which have lungs to take in oxygen from the air, fish have gills to breathe in the oxygen contained in water. This process of breathing begins when a fish gulps water through its mouth.

Detailed explanation-4: -Today we want to introduce you to Granddad, a 100-year-old lungfish whose unique respiratory system-having both gills and a lung-not only help him to survive, but may also be key to the evolutionary origins of the lung. Granddad is the oldest fish we know of anywhere in the world.

Detailed explanation-5: -Gills were present in the earliest fish, but lungs also evolved pretty early on, potentially from the tissue sac that surrounds the gills. Swim bladders evolved soon after lungs, and are thought to have evolved from lung tissue.