The correct option is 1
Explanation
Respiratory organs and mechanisms vary across different organisms, adapted to their specific habitats (aquatic, terrestrial) and biological complexity.- Pair 1 is Correct: Yeast is a unicellular fungus capable of surviving without oxygen. It performs anaerobic respiration (fermentation), breaking down glucose into ethanol and carbon dioxide in the absence of oxygen.
- Pair 2 is Incorrect: Frogs are amphibians that respire through their moist skin (cutaneous respiration), lungs (pulmonary respiration), and the buccal cavity. Tracheae are the respiratory tubes found in insects.
- Pair 3 is Incorrect: Fish possess gills as their primary respiratory organs to extract dissolved oxygen from water. Spiracles are the external openings of the tracheal system found in insects.
- Pair 4 is Incorrect: Insects respire through a network of air tubes called tracheae, which open to the exterior through spiracles. Gills are characteristic of aquatic organisms like fish.
Key Takeaway: Yeast performs anaerobic respiration; Insects utilize a tracheal system with spiracles; Fish utilize gills; and Frogs utilize lungs and skin for gas exchange.