water is the main source of energy for microorganisms.
water is the main source of energy for microorganisms.
what nutrient is the main source of energy for microorganisms?
water
many of the earth's elements and minerals (or mineral nutrients) are contained within the tissues and diets of organisms. hence, mineral and nutrient cycles trace food web energy pathways. ecologists employ stoichiometry to analyze the ratios of the main elements found in all organisms: carbon (c), nitrogen (n), phosphorus (p). there is a large transitional difference between many terrestrial and aquatic systems as c:p and c:n ratios are much higher in terrestrial systems while n:p ratios are equal between the two systems. mineral nutrients are the material resources that organisms need for growth, development, and vitality. food webs depict the pathways of mineral nutrient cycling as they flow through organisms. most of the primary production in an ecosystem is not consumed, but is recycled by detritus back into useful nutrients. many of the earth's microorganisms are involved in the formation of minerals in a process called biomineralization. bacteria that live in detrital sediments create and cycle nutrients and biominerals. food web models and nutrient cycles have traditionally been treated separately, but there is a strong functional connection between the two in terms of stability, flux, sources, sinks, and recycling of mineral nutrients.
food web
one of the most important features of chemostats is that microorganisms can be grown in a physiological steady state under constant environmental conditions. in this steady state, growth occurs at a constant specific growth rate and all culture parameters remain constant (culture volume, dissolved oxygen concentration, nutrient and product concentrations, ph, cell density, etc.). in addition, environmental conditions can be controlled by the experimenter. microorganisms growing in chemostats usually reach a steady state because of a negative feedback between growth rate and nutrient consumption: if a low number of cells are present in the bioreactor, the cells can grow at growth rates higher than the dilution rate as they consume little nutrient so growth is less limited by the addition of limiting nutrient with the inflowing fresh medium. the limiting nutrient is a nutrient essential for growth, present in the medium at a limiting concentration (all other nutrients are usually supplied in surplus). however, the higher the number of cells becomes, the more nutrient is consumed, lowering the concentration of the limiting nutrient. in turn, this will reduce the specific growth rate of the cells which will lead to a decline in the number of cells as they keep being removed from the system with the outflow. this results in a steady state. due to the self-regulation, the steady state is stable. this enables the experimenter to control the specific growth rate of the microorganisms by changing the speed of the pump feeding fresh medium into the vessel.
chemostat