What would happen if your earth is without green plants?

Then all animals that feed on plants, herbivores, would disappear. After which all animals that feed on the herbivores, carnivores and omnivores would disappear. Basically most of life on earth would go extinct, only bacteria and other simple organisms would survive. Also us humans wouldn't be able to stay healthy if there isn't enought plants to feed on(vegtables). Also plants provide us with oxygen, which is very important for respiration. without oxygen how would the organisms respire?