Why are gasses exchanged in the respiratory systems of insects and fish?

Question

Quizplus · Accepted Answer

Both insects and fish require oxygen as a reactant for cellular respiration and create carbon dioxide as a waste product of cellular respiration. Therefore, the exchange of gases is necessary for them to take in oxygen and get rid of carbon dioxide. Option A is incorrect because nitrogen is not involved in cellular respiration, it is mostly used as an extracellular gas to fill up the insect's tracheal tubes. Option B is incorrect because fish use oxygen as a reactant and produce carbon dioxide as a waste product in cellular respiration, just like all other animals. Option C is incorrect because although both insects and fish produce carbon dioxide as a waste product, this is not the only reason for gas exchange in their respiratory systems. Option E is incorrect because not all options are hurdles, and the question is not asking for obstacles or challenges.

Why Are Gasses Exchanged in the Respiratory Systems of Insects