Roger Y. Stanier and his colleagues came up with two categories of living organisms. This categorization was based on the type of nucleus present in their cells. The two categories are: (A) Prokaryotic cells – These are simple cells that…
Francesco Redi was an Italian scientist who conducted a famous experiment in the 1660s. Francesco Redi’s experiment was important in helping to disprove the theory of spontaneous generation, which the belief that life could arise from non-living matter. that helped…
There were two theories proposed for explaining the origin of life: spontaneous generation and biogenesis. The theory of spontaneous generation, also known as abiogenesis, was once widely accepted among ancient cultures and philosophers such as Aristotle. This theory suggested that…
UV light, or ultraviolet light, is a fascinating form of energy that comes from the sun. It’s not visible to the human eye, but some animals, such as bees and birds, can see it. UV light has a range of…
There are different methods for the preservation of microbial cultures. Bacteria preservation in glycerol is one of the common method for maintaining bacterial strains over long periods of time. This method involves adding glycerol to a bacterial culture and freezing…
Preservation of microbial culture is important because it helps to maintain the viability and genetic stability of microorganisms over time. In addition, it allows for the study of their behavior and characteristics and for the production of microbial products. Moreover,…
Pasteurization is a heating process used to eliminate or reduce harmful bacteria and microorganisms in food products, such as milk. It aims to improve food safety, preserve flavor and nutritional value, and extend the shelf life of the product. Pasteurization…
Moist heat sterilization is a method of sterilizing equipment, tools, and other materials. This process involves exposing items to high temperatures in the presence of moisture. Moist heat sterilization principle: Steam has high penetration power in the form of latent…
Tyndallization is an alternative sterilization method. It is a physical method of sterilization that uses moist heat (steam) for sterilization. It is also known as fractional sterilization and intermittent sterilization. Physicist Dr. John Tyndall invented this technique of tyndallization in…
Microorganisms in the genus Mycobacteria and Nocardia have complex cell walls with higher lipid content. The cell wall of these microbes contains mycolic acid, which is a complex hydrocarbon. Due to this waxy cell wall, bacteria don’t take up the stain easily. Therefore,…