Why do plants play the greatest role in the life of nature?

Plants are the most important group of organisms on our planet for two main reasons. First, oxygen, which is used by all other organisms for respiration, is produced, for the most part, by plants. Secondly, only plants are able to produce organic substances from inorganic ones and, thus, form the basis of all food chains of the planet. All other organisms receive organic matter by directly eating (or entering into symbiosis) plants or other herbivorous organisms.