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What is Northern blotting? Northern blotting is a technique in molecular biology that allows for the detection of specific RNA sequences in a complex mixture, offering valuable insights into gene expression patterns. In 1977, James Alwine, David Kemp, and George Stark at Stanford University introduced a method that was cleverly named “Northern blot,” referencing … Read more
What is Seliwanoff’s Test? Seliwanoff’s Test is a fundamental biochemical assay designed to distinguish between aldose and ketose sugars based on their structural differences. Named after chemist Theodor Seliwanoff, this test leverages the principle that ketoses (sugars with a ketone group, like fructose) dehydrate more rapidly than aldoses (sugars with an aldehyde group, like glucose) when heated with a … Read more
Gram-negative bacteria are a diverse group of microorganisms known for their unique cell structure, which plays a key role in how they interact with the environment and cause infections. Unlike Gram-positive bacteria, Gram-negative bacteria have a thin peptidoglycan layer sandwiched between two membranes. The outer membrane contains lipopolysaccharides (LPS), which can trigger strong immune responses … Read more
Gram-positive bacteria are a group of bacteria classified based on how they react to a lab test called the Gram stain. When stained, these bacteria hold onto a purple dye because of their thick, mesh-like cell wall made of peptidoglycan. This sturdy layer acts like a protective shield, unlike Gram-negative bacteria, which have thinner walls … Read more
What is McIntosh and Fildes’ Anaerobic Jar? Designed to provide an oxygen-free environment required for growing bacteria unable of surviving in the presence of oxygen, McIntosh and Fildes’ anaerobic jar is a specialist piece of laboratory equipment. Usually built from strong metal or glass, the jar has a firmly closing lid and has input and … Read more
The GasPak Anaerobic System is a laboratory method used to grow bacteria that thrive in oxygen-free environments, known as anaerobes. Using throwaway sachets filled with compounds like sodium borohydride and sodium bicarbonate helps to create an anaerobic (oxygen-free) environment more quickly. These molecules combine to generate hydrogen and carbon dioxide when water is introduced. The … Read more
What is BOD Incubator? BOD incubator Definition The BOD (Biological Oxygen Demand) Incubator is a specialized laboratory instrument designed to provide a controlled temperature environment, typically around 20 degrees centigrade, for microbial and biochemical studies, particularly for assessing the oxygen demand of microorganisms in water samples. BOD incubator Principle Operating on a well engineered mechanism, … Read more
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