Centrioles function as the major micro tubule organizing centers which is an important event in two major cellular processes - cell division and cilia and/or flagella formation. Given below is a description of the precise role of centrioles in each of these processes. Cell Division The pair of centrioles within a cell duplicates, and the two pairs migrate to opposite…
This lab activity uses a controlled experiment to demonstrate different rates of decomposition for a variety of man-made and natural materials. Microorganisms are ubiquitous in the environment, where they have a variety of essential functions. Many microbes are uniquely adapted to specific environmental niches, such as those that inhabit the Dead Sea (Halobacterium)…
The illustration shows a generalised bacterium with many of the main components illustrated. No real organism would have all of these features. The image above is 400 pixels across and the original is 5, 438 pixels across. CELL WALL The top half of the diagram shows a Gram +ve bacterium with its thick peptidoglycan outer wall closely apposed to the inner plasma membrane…
These are three bacterial motors with different torque (units of torque are piconewton nanmometres, pN nm). Credit: Morgan Beeby/Imperial College London Many bacteria swim using flagella - long tails that are attached to tiny motors made of proteins, just tens of nanometres wide. These motors spin the flagella, which work as nanoscale propellers to drive the bacterium…
Microbial communities perform key functions for the host they associate with or the environment they reside in. Our ability to control those microbial communities is crucial for maintaining or even enhancing the well-being of their host or environment. But this potential has not been fully harvested due to the lack of a systematic method to control those complex microbial…
The theory of molecular mimicry suggests that common pathogens, mostly viruses and bacteria, touch off autoimmune diseases when a person s immune system commits a colossal blunder, confusing foreign proteins with the body s own proteins. When immune system agents attack the pathogen, they also attack the body they are intended to protect. Pathogens like bacteria and…
As surface temperatures are expected to rise in the future, ice-rich permafrost may thaw, altering soil topography and hydrology and creating a mosaic of wet and dry soil surfaces in the Arctic. Arctic wetlands are large sources of CH4, and investigating effects of soil hydrology on CH4 fluxes is of great importance for predicting ecosystem feedback in response to…
A prokaryote is a simple, unicellular organism that lacks an organized nucleus or other membrane-bound organelle. Learning Objective Describe the structure of prokaryotic cells Key Points Prokaryotes lack an organized nucleus and other membrane-bound organelles. Prokaryotic DNA is found in a central part of the cell called the nucleoid. The cell wall of a prokaryote…
Bacteria cells function quite differently from human cells, from the function of the cell as a whole, right down to the individual structures in each cell. Bacteria exist in nature as individual cells. While some bacteria work together in a group, no bacteria forms multicellular tissues. Bacteria have organized structures within the cell, but do not have membrane-bound…
It began with what can only be described as an ingenious invention. It’s a fold-out sheet, with sticky tabs at the front and back, like a flattened starfish. The tabs stick to the loo seat. When in place, it forms a kind of hammock onto which the specimen is presented, ready for sampling. I slipped on the rubber gloves to prepare for the procedure. Once I had left…
It turns out, there are more reasons to love bacteria than to fear them — the latest being a the discovery of a new bacteria-based antibiotic that allows scientists to fight infections that kill hundreds of thousands of people each year! But there’s more to bacteria than their antibiotic qualities. Check out these nine facts — some of them may surprise you: This fact…
In case, the second best phylum shows ≥30% NOGs matching with the NOGs of the best matched phylum, the best phylum is selected by comparing the NOGs of the query genome with the classes present in both the phyla. The class with maximum number of NOGs matches is selected as the best class and its corresponding phylum is selected as the best phylum. In case, the top…
As gut bacteria garner more attention every day, scientists are starting to make forays into uncharted waters: the microbes of marine mammals. The collection of benign bacteria living within our bodies, our “microbiota, ” helps us digest food, ward off infection, and has even been linked to mood and behavior. Research on microbial communities has branched out from…
Fourteen years ago, during the darkest moments of the “stem-cell wars” pitting American scientists against the White House of George W. Bush, one group of advocates could be counted on to urge research using cells from human embryos: parents of children with type 1 diabetes. Motivated by scientists who told them these cells would lead to amazing cures, they spent…
