RESPIRATORY SYSTEM:-

• Frogs respire on land and in the water by two different methods.
• In water, skin acts as aquatic respiratory organ (cutaneous respiration- or cutaneous gas exchange or skin breathing, is a form of respiration in which gas exchange occurs across the skin or outer integument of an organism rather than gills or lungs.) .
• Dissolved oxygen in the water is exchanged through the skin by diffusion.
• On land, the buccal cavity, skin, and lungs act as the respiratory organs.
• The respiration by lungs is called pulmonary respiration.
• The lungs are a pair of elongated, pink coloured sac-like structures present in the upper part of the trunk region (thorax).
• Air enters through the nostrils into the buccal cavity and then to lungs.
• During aestivation and hibernation gaseous exchange takes place through skin.