Tag Archives: microbiology

Sulphur Cycle & Microbial Role in It

The sulfur cycle is the collection of processes by which sulfur moves between rocks, waterways and living systems. Such biogeochemical cycles are important in geology because they affect many minerals. Biochemical cycles are also important for life because sulfur is an essential element, being a constituent of many proteins and cofactors, and sulfur compounds can be used as oxidants or reductants in …

Read More »

Difference between: Environmental Microbiology

This series includes the difference table between Habitat and Niche Autochthonous and Allochthonous Neuston and Pleuston Habitat Niche A habitat is an ecological or and evironmental area that is inhabitaed by a particular animal, plant or other types of organisms. A niche is a term describing the role and position …

Read More »

Winogradsky Column

The Winogradsky column is a simple device for culturing a large diversity of microorganisms. Invented in the 1880s by Sergei Winogradsky, the device is a column of pond mud and water mixed with a carbon source such as newspaper (containing cellulose), blackened marshmallows or egg-shells (containing calcium carbonate), and a …

Read More »

Nitrogen Fixation & Root Nodule Formation

Nitrogen fixation is a process by which molecular nitrogen in the air is converted into ammonia (NH3) or related nitrogenous compounds in soil. Atmospheric nitrogen is a relatively nonreactive molecule that is metabolically useless to all but a few microorganisms. Biological nitrogen fixation converts N2 into ammonia, which is metabolized by …

Read More »

Nitrogen Cycle: Converting Nitrogen into Multiple Chemical Forms

The nitrogen cycle is the biogeochemical cycle by which nitrogen is converted into multiple chemical forms as it circulates among atmosphere, terrestrial, and marine ecosystems. The conversion of nitrogen can be carried out through both biological and physical processes. Important processes in the nitrogen cycle include fixation, ammonification, nitrification, and …

Read More »

Rhizosphere & Its Effects

Positive and negative interactions take place not only between microbes but also between microbes and plants. The rhizosphere is a zone of predominantly commensal and mutualistic interactions þetween microbes and plants. Plant roots provide such suitable habitats for the growth of microorganisms that high numbers of different microbial populations are …

Read More »

Interactions among Microbial Populations

Organisms living together in a community influence each other directly or indirectly under natural condition. All vital process of living such as growth, nutrition, reproduction required interactions between individuals of same species, or between species which are inter- and intra-related. Such relationships of individuals in a population of an ecosystem …

Read More »

Distribution and Sources of Air Microbes

Distribution of Microbes in Air No microbes are indigenous to the atmosphere rather they represent allochthonous populations transported from aquatic and terrestrial habitats into the atmosphere. Microbes of air within 300-1,000 or more feet of the earth’s surface are the organisms of soil that have become attached to fragments of …

Read More »

Microbiology of Air

Aeromicrobiology is the study of living microbes which are suspended in the air. These microbes are referred to as bioaerosols. Though there are significantly less atmospheric microorganisms than there are in oceans and in soil, there is still a large enough number that they can affect the atmosphere (like they …

Read More »

Rickettsia: The Disease Causing Bacteria (Part-1)

‘Rickettsia’ is a genus of non-motile, gram-negative, non spore-forming, highly pleomorphic bacteria that may occur in the forms of cocci, rods, or threads. The term ‘rickettsia’ has nothing to do with ‘rickets’, which is a deficiency disease resulting from lack of vitamin D; the bacterial genus ‘Rickettsia’ was named after Howard Taylor …

Read More »