Heterotrophic flagellates contribute significantly to the matter flux in aquatic and terrestrial ecosystems. Still today their quantification and taxonomic classification bear several problems in field studies, though these methodological problems seem to be increasingly ignored in current ecological studies. Here we describe and test different methods, the live-counting…
Abstract: From biofilm and colony formation in bacteria to wound healing and embryonic development in multicellular organisms, groups of living cells must often move collectively. While considerable study has probed the biophysical mechanisms of how eukaryotic cells generate forces during migration, little such study has been devoted to bacteria, in particular with…
Biological Agents, Work Practices, Safety Equipment, and Facility Design Specific to Each A very specialized research laboratory that deals with infectious agents is the biosafety lab. Whether performing research or production activities, when working with infectious materials, organisms or perhaps even laboratory animals, the proper degree of protection is of utmost…
Soil bacteria and soil fungi are the start of the soil food web that supports other soil organisms and the functions of a healthy soil. Diverse populations of soil bacteria and fungi can suppress root diseases. Soil bacteria and fungi are encouraged by ground cover and organic matter inputs. Populations of soil bacteria change rapidly depending on moisture, time of…
Photo credit: by Vanessa Ryan, Flickr: EOL Images. CC BY-NC-SA Introduction The word fungus usually evokes images of mushrooms and toadstools. Although mushrooms are fungi, the forms that a fungus may take are varied. There are over 100, species of described fungi and probably over 200, undescribed. Most fungi are terrestrial, but they can be found in every habitat…
Under traditional classification schemes Monera is the name of the Kingdom of Bacteria but in most modern textbooks, scientists due to the big diversity in the group that we normally call bacteria because there are such diversity, scientists are starting to split that into two other groups called Domains. One of these Domains is called Eubacteria, the other Domain…
The Baltimore system of virus classification devised by virologist & Nobel laureate David Baltimore is based on the genomic nature of the viruses. The central theme of Baltimore system of virus classification is ‘all viruses must synthesize positive strand mRNAs from their genomes, in order to produce proteins and replicate themselves’. The precise mechanisms…
Advertisement. EnchantedLearning.com is a user-supported site. As a bonus, site members have access to a banner-ad-free version of the site, with print-friendly pages. Click here to learn more. The cell is the basic unit of life. All organisms are made up of cells (or in some cases, a single cell). Most cells are very small; most are invisible without using a microscope…
Taxonomy, is literally the science of classification. Look at the picture above, and imagine that all those little divisions, like “firmicutes” are different phyla under the kingdom of bacteria. Then those phyla are further subdivided into different classes, then orders, then families, then genera, and then finally species! Take a look at how this works for one particular…
Daffonchio D, Thaveesri J, Verstraete W. Contact angle measurement and cell hydrophobicity of granular sludge from upflow anaerobic sludge bed reactors. Appl Environ Microbiol. 1995 Oct;61(10):3676–3680. Kjelleberg S, Hermansson M. Starvation-induced effects on bacterial surface characteristics. Appl Environ Microbiol. 1984 Sep;48(3):497–503. Lindahl M, Faris A, Wadström…
This chapter will look at different types of microorganisms. It will discuss their cell structure and functions. It will also discuss the position of microbes in food chains and their role in the biosphere. Archaea (bacteria) Archaea were once thought to be a type of bacteria. After extensive research of their DNA and membrane structure, some scientists decided to…
This is clearly beneficial to the F-plasmid, since its genes get replicated, but why is it useful to the bacteria? The F-plasmid often contains useful genes that deal with stressful situations that have recently arisen, for will spread this resistance to other bacteria. Since the F-plasmid can integrate into the host s chromosomal DNA it can, upon leaving, take away…
Archaea versus Bacteria comparison chart Archaea Bacteria Ribosomes Present Introduction (from Wikipedia) The Archaea constitute a domain or kingdom of single-celled microorganisms. These microbes are prokaryotes, meaning that they have no cell nucleus or any other membrane-bound organelles in their cells. Bacteria constitute a large domain of prokaryotic microorganisms…
Pandas eat almost nothing but bamboo, but find it hard to digest. Aram Williams / Alamy Giant pandas don t digest bamboo by themselves. Microorganisms in their guts may help the endangered animals to subsist on plants despite a gut that is better suited to eating meat, finds an analysis published this week in the Proceedings of the National Academy of Sciences. Pandas…
