a Production of food: cheese, yogurt, vinegar, wine, sour cream, etc. b Industry : cleaning up petroleum, remove waste products from the water, synthesize drugs and chemicals. Symbiosis : The interdependence of different species, which are sometimes called symbionts. There are three main types of symbiosis, based upon the specific relationship between the species involved: mutualism, parasitism, and commensalism. Symbiosis that results in mutual benefit to the interdependent organisms is commonly known as mutualism. An example of mutualism is the coexistence of certain species of algae and fungi that together compose lichens. Their close association enables them to live...
function in the presence of oxygen, and bacteria of the genera Klebsiella and Bacillus, which function without oxygen. Some forms of cyanobacteria formerly known as blue-green algae also fix nitrogen, such as the alga Anabaena, which, in symbiosis with the water fern Azolla pinnata, is said to markedly increase rice yields, as was the case in paddies in the Thái Bình region of northern Vietnam. The need for fixed nitrogen in agriculture today is far greater than can be supplied by natural biological processes, and the production of nitrogen compounds from atmospheric nitrogen is a major chemical industry.