I think the biggest effect would be starvation, not atmospheric. Herbivores would have less food and would thus provide less food for carnivores, and the food chain would collapse from the bottom up. At the very least it would trigger a mass extinction.
ok what the whole disappearance of autotrophs has to do wit cell respiration is that without the plants that animals eat they wouldnt get energy that is gained by the breakind down of glucose into water and carbon dioxide
