NEET PG DENTAL EXAM

Detailed explanation-1: -The thin membranous skin is allows the respiratory gases to readily diffuse directly down their gradients between the blood vessels and the surroundings. When the frog is out of the water, mucus glands in the skin keep the frog moist, which helps absorb dissolved oxygen from the air.

Detailed explanation-2: -Most amphibians breathe through lungs and their skin. Their skin has to stay wet in order for them to absorb oxygen so they secrete mucous to keep their skin moist (If they get too dry, they cannot breathe and will die).

Detailed explanation-3: -Amphibians usually have a smooth, slimy, and permeable skin that allows water and air to pass through it. Some amphibians are adapted to be fully aquatic and never leave the water. Aquatic species live in the water for most or all of their lifespan and many have gills that allow them to breathe in water.

Detailed explanation-4: -Adaptations of the alveoli: Moist walls-gases dissolve in the moisture helping them to pass across the gas exchange surface. Permeable walls-allow gases to pass through. Extensive blood supply-ensuring oxygen rich blood is taken away from the lungs and carbon dioxide rich blood is taken to the lungs.