In my honest opinion, i would think it would be the C the burning of plastic in open burn barrels I am only saying that because my asthma acts up when there is fire or smoke and I think that's the best option.
Insertion or
of genes to produce desired proteins.
Answer:
Tubules?
Explanation
The trachea, spiracle, and air sac are part of their respiratory system, Howeber, the tubules are what take away the carbon dioxide from their system. Im not sure if they produce the carbon dioixde. But they are a part of what removes the carbon-dioxide from their body.
